Reef-Farm operations

[raaden]

Quick update on the CA sand before I start giving some first observations on the operation so far.

I have found the sand and unsurprisingly it is available just about anywhere large scale animal farming is done. I found this out by a huge chain of talking with chemical suppliers who sent me down a line where I finally found a plant that distributes it by the bag and it is not even 3 hours away. Unfortunately it is calcitic (vs. oolitic), and it is calcite (vs. aragonite) so like Mr. Wilson said earlier I will not get any buffering benefits, but I will be dosing anyway so that shouldn't be an issue. My primary concerns were nitrogen cycling (to keep nitrates up and ammonia low) and to help with benthic zoo populations. It should work great for that.

FYI if anyone needs more info let me know I have found three regional suppliers, but from them you can find even more. Most places will tell you that you are too far away for them to supply to you and will recommend someone closer. The only issue is that it seems to only come from about 5 places in the country and you will end up paying for shipping twice if you are too far away. Oh and one other thing, this is for very large orders only. They won't help you with a few bags (<50 bags). Everyone I talked to needed a minimum order of a pallet (64 - 50# bags).

The articles ref'd above are very good and if you are looking for info on this part of the equation they are a great place to start, thanx WD and Mr.W.

[BallaBooyeaH]

Not wanting to hijack this thread but if anyone has feedback for starting a venture in a existing GH and can shed some light on my idea's - Please check out a new thread I have started.

Post is here.

http://archive.reefcentral.com/forum...readid=1179420

Raaden, You out of all the threads I have followed seem to be making the most progress. Oh what can be done when you are not married with kids....

Look great and keeps inspiring me to start

[raaden]

Balla,

Oh, but I am married with Kid, and one thing I forgot to put into the business plan was the expenses of sending the wife and daughter to the mall and movies all the time so that I can get stuff done in the GH . That has been very expensive and completely unexpected.

[kaptken]

Were you thinking of these two articles by Rob Toonen testing various types of sand beds for denitrating efectivness?

http://www.advancedaquarist.com/2005/6/aafeature

and part two

http://www.advancedaquarist.com/2005/7/aafeature

or perhaps these older articles on plenums.

http://www.seabay.org/art_plenums_part1.htm

and

http://www.seabay.org/art_plenums_part2.htm

I have used many plenums and have had some good luck with them. But like everything in this hobby, opinions vary.

[raaden]

KaptKen,

Nice find... I believe those are the articles (Toonen et al)I was referring to (especially the later section of the second part of it). I reread it again this morning and it has me thinking some more about some things I might want to do with the sand bed (always a dangerouse proposition).

--All,

I do have an update coming, but we have been getting record heat and humidity here and it has been all I can do to try and keep the few inhabitants I have happy. Once things cool off (hopefully in the next day or so) I will have some pretty interesting finds.

[mr.wilson]

Toonen is a little less cocky in the second article, In the first one, he boldly states in his summary the you need a BS detector to guard you against any findings that vary from his; while the second article is peppered with admissions that his study was conducted over a relatively short period of time (118 days), that mortalities affected results, and there were too many variables to make concrete findings of some aspects. These shortcomings are of no fault of his own, as it's a very difficult experiment to govern the controls of.

The first article made bold conclusions, while the second one focused much of the attention on defending the accuracy of the first. Much of the attention was given to the similarities of the results of the chemically dosed treatments and the live animal treatments.

It's hard to measure the value of anecdotal evidence and its' source. His scientific approach is welcomed even with the studies limitations and the chemical evaluation of the test water for each treatment are indisputable. Obviously, a fine sediment has a higher dissolution rate than a larger one, resulting in higher PH, calcium, and carbonate values; however, the relatively short duration of the experiment and lack of controls for the live animal treatments (such as, feeding varying amounts to each tank, mortality, and ranging biodiversity and condition of animals) will skew these results.

It takes at least 21 days for bio-films (bacterial slime) to start to coat sediments and rock. Bio-films grow one layer upon another, with a sloughing-off as the layers get too thick or with wash-off (physical damage caused in collection, and by sediment infauna). As one granule is crashing, another is flourishing, in a constant cycle. In addition to this, sediments can become calcified at the surface and further lose solubility. Sedimentation (detrital build-up) is another process that takes a few months to have an impact on the system. Eighty percent of nitrifying and denitrifying bacteria develop on detritus, and not directly on sediments, rock and other surfaces. I don't think a 118 day study is a fair representation of sediment conditions experienced with a well established reef tank or mariculture facility. Anyone with a DSB will tell you it took many months to culture enough pseudomonas (denitrifying bacteria) to reduce nitrate to 0.

Sediment infauna have a similar growth rate. The sediments in Toonens study were inoculated with benthic invertebrates (unspecified "sediment infauna") that we will assume were worms (fan, bristle etc.) and zooplankton (copepods, mysids etc.). I know from my observations of remote plenum-like "benthic zones", it takes six months to a year to fully populate them. This is by no means proof that plenums serve any benefit, but it demonstrates that they need sufficient time before any judgments can be made of their merit.

There were a few mortalities during his study. There were 2.91 (on average) unidentified animals (urchins, snails, crabs, or puffers) that died in shallow sediment tanks, while only 1.47 (on average) died in deeper sediment tanks. I'm not a scientist or statistician, but I have quite a bit of experience in animal husbandry, and feel it's an unfair conclusion that shallow sediments cause increased mortality based on those numbers, yet he makes this very claim in the article.

The water quality was very close within all of the tanks, by his own findings, so the mortality could not be attributed to these parameters. This leaves only pathogens as the causative agents. Perhaps an experiment testing the hypothesis of sediment depth fostering the proliferation of pathogens could yield concrete findings, but there were far too many unavoidable variables in his study to draw those conclusions. I'm certainly not going to add 2.5" of sand to my 1" substrate in the hopes of lowering mortalities, as nice as that would be.

As Raaden has mentioned, he will be chemically dosing for calcium, carbonate, and magnesium supplementation, so dissolution rates and composition comparisons of calcite vs. aragonite are moot. I believe Dick Perrin at Tropicorium uses aragonite exclusively to maintain calcium and alkalinity, but I'm not sure how he achieves this, as every reef aquarium I've experienced requires supplementation of some sort to meet NSW (natural sea water) levels.

A deep sand bed (>5") will provide anoxic conditions (hydrogen sulfide build-up) whereby localized acidity (lower PH), caused by bacterial byproducts, will dissolve aragonite or calcite more readily. Aragonite starts to dissolve at a PH of <8.4, while calcite must be <7.8 PH before it starts to dissolve. A PH of <7.8 is easily achieved in a deep sand bed, especially at night when carbon fixing (photosynthesis) ceases and respiration produces Co2 (carbonic acid). The more photosynthetic activity during the day (oxygen production), the more respiratory Co2 production you will get at night, unless you have a reverse photoperiod refugium to balance the equation. Even in the best of conditions, testing and supplementation is still necessary.

The aspect of removing, or at least reducing, nitrate still remains for Raadens application. Toonens study, despite its' limitations, seems to indicate that a 9mm (3.5") coarse sand bed is basically as effective as a fine sand bed of equal depth, or a shallow one for that matter. This is comforting information, considering 3.5" is nowhere near the common standard of a "deep sand bed" of >5", and in many cases, >12". He was able to get nitrate levels close to 0 in all of the live animal treatments in a 90 day period, which is a feat in and of itself, not to mention this was accomplished without any means of nutrient export, chemical, or mechanical filtration. Nitrate started to climb after that point, which may be due to detrital build-up, as that's about how long one would expect it to take.

The benefit of a cheap substrate (calcite for example) is that it can be periodically replaced to export bound silicates and phosphates. This practice will not only act as a passive method of export, it also doubles as a means of producing aquacultured live sand. If you can develop a market for your "old" cultured sand, it may warrant paying the extra money for a more desirable media, namely aragonite. In other words, get your customers to pay for your nitrate reduction and phosphate absorption media. If you offered a coarse substrate with coraline algae and proven nitrate reduction capabilities, you would have an instant demand for your product. Even a reef rubble substrate (1" - 2" dia.) could be introduced. You just need to come up with the slick titles like Samoan Pink or Tahiti Treat.

I'll let you use your BS detectors to evaluate my comments.

[raaden]

Mr. Wilson, very nice summary of the article. Your reflections on the DSB are exactly what I was thinking about. If I can get a depth of 6" I might start to get some benefit from the Calcite. Somehow I never thought it got that acidic on the bottom of a DSB, either way I will still be dosing just in case.

AFA the exporting of the sand, one thing I have been contemplating is changing a portion of the sand bed occasionally to use as the sand medium for making the rockwork. The more I read about oyster shell the more leary I am of using it in large quantities in the vats. I am not sure if there is a market for live sand, but I guess I could make it available and see what happens. I still haven't had any response from the contacts for Aragonite so I have decided to go with the calcite for the substrate and I think it will work fine. I still have to try to get ahold of WhaleDrivers (I think it was him) suggestion for the miami rubble. I think that would work out nicely as you mentioned for putting a rubble layer on top of the sand. That way it would act as a landing zone for small fraglets that always seem to get lost from their homes.

P.s. I am going to claim the Tahitian Treat if noone else does

[Whaledriver]

MARCONA OCEAN INDUSTRIES LTD
904-646-3595
4018 Retford Dr
Jacksonville, FL 32225

These are the guys mineingthe sand in the Bahamas. You should be able to buy the sand in 5 ton bags that can be trucked to your site. Mention that its for agriculture use. Don't mention anything about aquariums! You might do some research with sand dealers in the area before you try to get it from them. The others in the area should give you the info you need to make a simple purchase. Someone local must be using it for cement, drainage, pavers or soil ph adjustment

[raaden]

Well it is update time again, unfortunately there aren't any pics for this one. I have to either get a better camera (DSLR) or figure out better ways to use the one I have because I have taken a ton of pictures but none of them seem to come out underwater. You will just have to take my word on this one.

I will hit the highlights (or high temps as the case was) first and then pickup from the previous update. Last week was quite a tough one in the greenhouse, the weather was absolutely ridiculous around here, and by ridiculous I mean 4 straight days of record high temps. What started out as a forecast for a record day turned into almost a week of unbearable temps reaching a peak on Thursday of 104 with 60% humidity, and the other three days were all over 100 with 40-60% humidity each. The ambient temps in the GH reached 112 and I must have drank 3-4 gallons of liquid each day without going to the bathroom once. I am happy to say that the farm made it through incredibly well considering the expectations. When looking at the weather, I kept thinking "this stuff can't take another day of this", but everyday at the end of the day most everything was still there sweating it out with me. I have definitely identified some Reef-Farm superstars, and some others that may not be suited quite so well.

The last update ended with the first responders being sent in to put a little life into the tank. They did just fine and after another couple of days the ph went down to 8.3 so it was time to start stocking. I started with just a few frags that I had been keeping in my 'fuge in preparation for this. The initial set of frags were a few different kind of zo's, some xenia, a few rics, a spare caulastrea, and a giant leather that since I have gotten it has never really filled out so i was hoping that the greenhouse might change that.

I built some stands for the eggcrate out of pvc pipe, much like what Steven Pro did with his setup. Since mine were going to have to hold 2.5 sheets of eggcrate I made them a bit more permanent with legs and a crossmember, and so far they are holding up quite well. It looks like I will get about 5 sheets of eggcrate into each vat leaving some cracks inbetween the sheets for the fish to get into. That put the working space at ~40sf per vat or about 400sf for the facility which is just a touch lower than I had envisioned, but should be more than enough.

The initial stock went in 8 days before the heat wave started and most of it was looking good. The biggest thing I noticed right away was that the xenia, zo's and rics were definitely showing signs of photoinhibition, but I expected this. I decided to go without shadecloth this summer partially because I figured it would be so close to the end of the season by the time I got any stock in, and also because shadecloth installation and removal on the greenhouse is almost a day long job for three people and I didn't want to risk any mishaps with the plastic. This way I can also do some looking into the top end of what the worst case scenarios are for heat, light and other parameters.

The rics fared the worst, and never really acclimated well to the vats. They almost all melted or came off the baserock and took a dive into the rockwork below. The ones that survived never really opened up, and I am guessing they are just surviving for now.
The xenia almost all survived but didn't open up much except for first thing in the morning, and late in the evening, but when they do they pulse the whole time and otherwise seemed to be looking pretty good. They have definitely changed physically as the bases on all of them have gotten noticably thicker and the stalks seem to all be coming off directly straight up.
The zo's all seemed to be doing very well considering they don't open up much either. The frags all stayed pretty much closed, but did occasionally open up during the day. The ones on the edge of the baserock pointing to the side or coming out from under the rock open up much more and stay open almost all day which leads me to believe that the top facing polyps are just over exposed.

The leather on the other hand was absolutely happy as can be. within a day of going to the greenhouse it started to fill out well, and the edges that always drooped down started curling up and lobes that I never even saw started pushing out from the bottom rim. This was just your run of the mill Leather (I think it is a fiji finger leather) that was a light brown and looked decent. Now it looks absolutely great. It has started to take on a more fleshy/red color and it getting lumpy all over. It has expanded in size about 50% since going into the greenhouse and hasn't shown any signs of photoinhibition at all.

[Philip Root]

I decided to go without shadecloth this summer partially because I figured it would be so close to the end of the season by the time I got any stock in, and also because shadecloth installation and removal on the greenhouse is almost a day long job for three people and I didn't want to risk any mishaps with the plastic

What type, and how are you using your shade cloth? I put mine on and off by myself and it takes 20 mins at the most.

As far as the temps go, we are in our 10th day of over 100, We have never had this type of heat. I did have to mod my sps tank to run cooler. I made a trey to put on the intake of my fan that has mag flake in it. The mag flake will dry the air and cool the water very well. You could use CaCl if you did not have mag flake. Befor I used the mag flake I was runing about 80.9. After the magflake 78.3.

Philip

[mr.wilson]

You mentioned that the GH reached 112 F, but how high did the water in the vats actually get?

Did you add extra shade, air circulation, or air lifts to combat this heat wave?

Have you looked into a water storage container that can be buried into the ground? A series of 50 gallon drums would work just as well and cost less. They would be shielded from direct sunlight and insulated from the greenhouse effect going on above them. It's a passive form of geothermal cooling, but may come in handy in case of emergency. The only problem I can see, is you may need a 10 to 1 ratio of stored (cool) water to keep up with the demand.

You should take a look at Peter Wilkens books to see the temperature swings he measured in shallow reef flats. He also provides a list of species that are exposed to air at low tide, including some leathers.

Deep water species like caulastrea and some ricordea species (particularly Yuma's) haven't adapted to temp swings in their evolution.

Anything that bleaches should bounce back quicker in a GH, than it would in a home aquarium, but the sun can be relentless.

[raaden]

WD, have you tried to get ahold of them. The last thing I heard about Marcona was that they sold out to another company that makes tanker ships or something like that. The guys that didn't go with them started up AragoniteSource LLC and are the ones that I haven't had luck getting return phone calls from. I will try to get in touch with them tomorrow and see what happens. I also have a bunch of other numbers for Marcona in Ga, SC and somewhere down south in Florida but all said they were no longer bringing in the product. I will try that number though as I don't remember anything from Jacksonville in the list

Philip,
Yikes!!!! I don't think my setup could make it like that. How is the outside humidity? That was the worst part here, the days when it reached 100's but the humidity was low were not bad and temps in the GH stayed in the upper 80's, but when the humidity came in everything got hot. The other part that made a huge difference was that the hottest days there were no clouds in the sky so the sunlight was drowning the greenhouse with heat. From what I have seen so far it is not the outside temps that do the worst it is humidity and cloud cover. When the humidity stays under 50% and there is some cloud cover it is always cooler inside the GH than outside. Another reason why I need shadecloth
Right now I am not using shadecloth, but I am going to use the blue cloth that you are going to use next summer. I wanted to use a white shadecloth but I have heard bad stuff about its ability to last a whole season. We have mag flake here but it would be difficult to use with the evap cooler taking up the whole wall of air inlet. Overall I am pretty happy if that is the worst that we run into. The next part of the update will explain it more, but everything did pretty well.

Also what did you change around on the sps and what are your tank temps like with the heat.

[raaden]

Mr. Wilson,

Do you have a name on that book, I would love to take a look at it. I am currently trying to get my thoughts together on temps in the vats, but from what I am seeing the thoughts that temps must stay constant at xx.x degrees don't seem to apply to many different species, while it completley applies to others. I will elaborate more later, but I have definitely seen a floor and ceiling to what is tolerable (and they are very hard limits), but nothing has seemed to mind the temp shifts at all... and they have been extreme.

It would seem that shallow water species would undergo extreme temp shifts from low to high tide, and day to night. Deeper species probably not so much as there is much more insulating water, but I still have to think that there is some fluctuation in the water temps even at 20-30 ft. I know from surfing that some undercurrents are atleast 15 degrees cooler than the surrounding water.

Anyway this is something that I am definitely going to do some research on and hopefully come up with some useful results.

[Philip Root]

The changes I made was the magflake. Just on the the fan that is blowning air on the tank did I use the magflake. I use some squirrel cage fans that pull air from the side to cool each tank. so the side as mag in it. The air is very dry and the air that comes off the tank is really cool.

The Humidity is all over the place. In the am it may be as high as 80% but as the day gose on it starts down. to around 40%-50%.

[raaden]

Ah-ha that is a really good idea... I'm not sure about drawing the air in from the outside, but the tray for the outlet of the fan is a great idea. Are the fans pulling air through the plastic or do you have a large manifold running from somewhere. I just don't think I would like putting a bunch of holes in the plastic. The inflator fan for the plastic does this, but...

since I am only a mile or so from a huge lake our humidity actually gets worse as the day goes on (or in reality it just doesn't go any lower), so when the lake gets hot after a few days of sun and heat the humidity here just keeps going up.

[mr.wilson]

It's a two book set, but the info you want is in "Invertebrates, Tube-, Soft- and Branching Corals", by Peter Wilkens & Johannes Birkholz. I would get the set if you can, as their both chalk full of information and now out of print.

If your German is good you can get the original "Niedere Tiere, Rohren-, Leder- und Hornkorallen" (damn that rolls off the tongue smooth ).

It was the first book in the hobby to give a glance at the natural environment of the stuff we keep. Once you get a look at the landscape, it's much easier to paint the picture.

In it he describes how Sarcophyton Trocheliophorum experience a temperature range from 75 F to 104 F in just a few hours. He goes on to describe the PH shift (8.35 - 8.45), salinity drops to 1.016 after rainfall, redox values between 135 mv & 192 mv, and lux readings of 2,800 in the morning, 14,000 at 11:00 a.m., and 17,000 to 22,000 with occasional 26,000 lux peaks according to cloud cover between noon and 2 p.m.. He reports that the lux values drop to 9,000 and 7,500 at 6:00 p.m..

[mr.wilson]

Originally posted by Philip Root
The changes I made was the magflake. Just on the the fan that is blowning air on the tank did I use the magflake. I use some squirrel cage fans that pull air from the side to cool each tank. so the side as mag in it. The air is very dry and the air that comes off the tank is really cool.

The Humidity is all over the place. In the am it may be as high as 80% but as the day gose on it starts down. to around 40%-50%.

Can you regenerate (dry out) the mag flake? Can you tell when it is spent?

How does it perform compared to silica gel or other desiccants?

[Philip Root]

The air dose not come from outside, just the side of the fan. ( not from behide like most fans)

Magflake turns to water. ( i currently collect it in a bucket) I don't know if you can dry it out? I personaly think it dose better than most desiccants, but has to be refilled.

[raaden]

Unless I can get my wife to read the books to me I will have to go the English route. Thanx for the info I will put them at the top of my Amazon list.

I am not sure what makes up MagFlake or if it is different than others of it's type but the reaction is chemical. If memory serves it strips the Hydroxide out of the latent moisture and breaks down in some way. I have seen it work great, but I don't think you can regen it as what is left is not the same stuff as before. I am pretty sure if you dry it out it will be different salts. The other thing about it that is good is that it produces much less heat to do the job than other dessicants.

I might have to try it if we get another week of oven temps.

[raaden]

With the frags all seeming do ok with the vat conditions (except the light), I decided to gets some initial broodstock and see what would work in the greenhouse. I mostly looked for things that were more hearty to start with and will get into the prettier things after the vats have had some time reach an equilibrium.

The shopping list was as follows: Purple Montipora (this sort of qualifies as pretty and I didn't intend to get anything like this, but when you find a deal on this guy you have to take it ), some assorted green mushrooms (rics and discs), 4 more types of polyps (mostly zo's but one nice sized bunch of palys as well), A goni that someone was trying to get rid of, some cespitularia, a chunk of GSP, Neon mumps leather (I only got this since the other leather was doing so well), a few acros, a bunch of feather dusters, and a gold crocea (just to see what a clam would say). Had I known that we were going to get a tradewind direct from Hades I would have held off but Monday was supposed to be warm (92), and Tuesday was supposed to be the only really hot day (101) before it cooled off, so I got the stuff to be delivered the previous Friday so it would have some time to acclimate before the hot day came.

I was already planning a quasi heatexchanger that was fed from the water going to the evap wall, and thought that might help out some. I was also planning a window fan blowing across the top of the vat so that I could use whatever evpaporation I could get, but if it only lasted one day I could even just load the tank up with ice instead of makeup water that day and keep it cool. Great ideas in principle but when Mother Nature wants to test your limits, principles don't always hold up. Anyway I got the stuff in and most of it looked pretty good, but the goni and one acro just didn't look too good at all. In hindsight I should have put the goni into the display tank for a few weeks, but I thought maybe the sunlight might help it.

I took most of the day acclimating the stock with 50-50 makeup water and vatwater, since I still wasn't too confident that the tests were completely accurate. By the end of the day everything was in the vats and the only other thing that wasn't looking so good was the rock of rics. The clam surprised me and once I put him into his sandbox he popped right open and started feeding. When he first opened up his mantle was a slight greenish brown, and the rest of him was a light orange, not looking great but he did look healthy and was open so I figured it was doing alright. I also decided to take a kenya tree frag out there that evening since it was doing really well in the fragtank and I wanted to see how it would react.

Saturday should have been a wake up call as it was much warmer than expected. It reached the mid 90's and the humidity was pretty bad. It was by far the hottest day in the greenhouse since the fans were installed. I hadn't yet put the fan on the tanks or installed the heat sink, even still, surprisingly, the tanks were doing pretty well. That morning they were about 76 when I got out to check them and at 530 they were still only about 82. This really surprised me, I knew that 600G of water would make for good insulation but I never expected to only get that little of a temp change. That evening I looked at the weather and what started out as a '1 day temporary heat wave' had now turned into two days of near record temps. I was starting to get a little worried so I installed the heat sink, and mounted the fan. I really didn't know what to expect from the coming heat.

Monday temps reached 100, luckily the humidity wasn't bad, and Sunday night was cool so the tanks started cooler than they had been. The evap did a great job at keeping the gh cool and the fans were working on the tank. I don't think the heat sink is doing much, the run through the tank is a bit too short to really get any temp conversion. The inlet temp was running about 62, but the outlet temp was only 2 degrees cooler so there wasn't much heat being absorbed. It will stay in there for now but I don't think I will use it for any of the other tanks. The tank temps reached 83 at their peak, but nothing seemed any more stressed than it already was, although the rics were not doing well, the goni still hadn't shown any tissue, and the one acro was just about gone. The zo's and leathers were looking fine, although the green mumps had a bit of mucus collecting on it in some places where the green was coming back. The monti had a bit of recession on the edges, but the purple color was looking better than when I got it. The clam was still... well, happy as a clam (sorry, you knew it was coming at some point though). All in all the first day of furnace exposure went pretty well.

[raaden]

Monday even comes and goes and things went pretty well. I was relieved to know that the vats wouldn't become heat sinks and boil in the sun, and the evap cooler was doing a phenomenal job of keeping the greenhouse cool. It was noticably cooler in the greenhouse than it was outside (88 vs. 100). Before I went to bed I looked at the weather to see what it looked like as the week was going on and it wasn't looking good. They were now forecasting temps to stay above 100 for the rest of the week and finally cool down Friday evening. Tuesday wasn't going to be quite as hot as expected (only 101 instead of 103) but Thursday was going to be a scorcher with soupy humidity.

I was a bit worried, as I had just loaded up some pretty nice stuff, and there was no way I could get it all into my display tanks since they were already overfull of frags. I decided to ride it out, take lots of notes and if nothing else make a learning experience out of it. Monday night it again cooled off a bit which did a great job of taking the heat out of the water, and Tuesday morning the tanks were about 77degrees. I put a few bags of ice in the freezer just in case, and started watching. By the afternoon you could tell that the humidity was higher since the evap cooler was not doing quite as much to cool off the air as it was the day before.

Still it only reached 91 in the Greenhouse and the tanks only got to just under 84. The roll call was pretty much the same with one exception another acro was not looking good. It started getting lighter in color on Monday but I thought it was starting to color up (it started brown... but don't they all ). By tuesday night you could tell there was no color coming it was just receding. The strange thing was that the tips still had polyps out but the base was not looking good. The goni was receding a bit as well, but the other areas were looking nice and it was starting to look more fleshy.

It didn't cool down nearly as much Tuesday night and the tank temps were 79 to start the day on Wendesday. I knew that was going to be trouble. I put a bag of ice in Wednesday morning and it did absolutely nothing to the temp. 10 minutes after the ice melted the tank had changed 3/10ths of a degree... Now I was worried. It was now starting to dawn on me how much heat was really stored in 600G of water. I threw every bottle of liquid I could into the freezer and tried to think of other things I could do to cool the tanks. I even contemplated going to the LFS and buying a ridiculously overpriced chiller, but then I went back to the research angle and decided the information might be just as valuable. I decided I was going to let the temps go up but control them with whatever I could get that was frozen and just see what happens.

Granted it is not a scientific study, but it might just be some good information that I can use later. I did nothing for most of the morning, just monitored the temps to see how they rose. By 1 pm the temps were up to 83, but nothing seemed to be reacting to it. At just over 84 the zo's were all closed up, even the bottom ones in the shade of the rest. The xenia had completely closed up tight (or atleast it seemed tighter than before). I decided to try and cool it down a bit and loaded it up with a rubbermaid container full of ice on the opposite end of the vat from the corals. This was more than 60# of ice and it melted in about 25 mins, but it did bring the temps back down to just under 83.

Nothing really changed as the tank cooled down, but it went back up again. This time it reached 84 again as the sun was just starting to hit the treeline so I didn't bother to try to cool it down as it would start to cool off on its own soon. That night it was warmer than the one before and the exhaust fans didn't shut off all night... (or were alteast on at 6 am which hadn't happened before) they are set to shut off once the GH reaches 74 and I am not sure it ever made it there even though the evap cooler was dry (had been off for a while) and it turns off the water supply at 77. Most everything was still doing alright and as things cooled off and the sun went down the xenia and zo's came out again and seemed fine. The one acro was already bare and the second was not far behind. It was pretty evident it was not doing well. The goni still had not shown any tissue, and now the Kenya tree was completely shriveled up down to a tiny stump. I am not sure when this happened as I put it in a shady corner and forgot to check on it throughout the day. It never really came back either once the sun went down and the temps cooled off a bit. The rics were on their way out but they never really looked good to start with so I am not sure what was the cause there. The discs looked about the same although some of them came off their rocks and were lost into the rockwork. Who knows maybe in a few weeks they will attach and start to grow... Sweet bonus frags!!! But the leathers and the clam were still doing absolutely fantastic. The green mumps was starting to show more and more green and getting more and more bumpy.


Thursday morning the tank temps were 79 at 6 am and all I can think about is that it was going to get ugly. Weather was expected to be the worst yet with 104 temps and 65% humidity. I couldn't even imagine what was going to go on in the Greenhouse. I had alread seen that 84 seemed to be the point where bad things were happening atleast for some stuff, and I wasn't sure that I could keep it below 84 with the vats starting at 79. I put another 60#+ of ice in and that got it down under 78 but it would be shortlived. By 11 am the temps in the greenhouse itself were getting bad as it was already 100 outside, and inside it was getting into the upper 90's. This was the first time since the cooler was installed that this was happening. Humidity was a solid 65 based on the sweat that was pouring down me constantly, and it seemed that I had reached the saturation point of the evap cooler. Water temps were already 82.5 and there wasn't a cloud in the sky to shade us either. I had frozen up a few bottles with water and some milk jugs just in case I needed them, and I put one last tub of ice into the vats. By 1pm it was 101 outside and every bit of 105 inside. The vats were very near the 84 point and I decided to see what was going to happen if it went past there. I had about another 60# of ice between all of the frozen bottles and the couple of bags I still had left, and decided unless everything started to look bad I was going to use that to cool things down once the sun broke the trees.

The last few days the temps were peaking out at about 4 pm and the sun hits the trees sometime after 6 so I decided I would save the last of the ice for 530'ish. It was supposed to cool off on Friday and there was rain in the forecast so I just hoped I could get through this day.

[kaptken]

Hey Raaden.
If i recall your GH construction pictures, you have a pretty large open field area next to the GH, why not do a passive geo thermal cooling system. if you have access to a backhoe or a friend with a trencher , why not just bury a thousand feet of pvc tubing about 6 feet down, coiled or length wise in trenches for a heat sink. I think the rule of thumb for burried tubing for geothermal heat pumps is about 600 feet of 1 inch tubing for each ton of chilling capacity. but since you are not having extreme heating you may not need that much for the hot months. just enough to cool it down a few degrees to keep the system below a max of 82.

then you just need a heat exhanger for the ground loop to cool the sump salt water. a Quiet One 4000 pump, 50 watts, 1000 gph, might do the trick for circulation thru the ground loop. or something like that. for safety of leaks, you could even use normal salt water for the ground loop. then no chance of diluting the tanks by a leak. and it probably wouldn't freeze in winter.

Just brain storming. stuff I might do.

But now my brain hurts...

got to go.

Bye...

[raaden]

So far the sun had been hitting the greenhouse full force, with almost no clouds in the sky. One thing that made a huge difference was when a stray cloud blocked out the sun for a minute or two you could tell a huge difference in the temps in the greenhouse. It would cool noticably and quickly, but then the sun would come out and beat down again. Unfortunately there would be no cloud cover until Friday.

By 4 pm the temps in the greenhouse were pretty rough. The ambient temp was was 112 and I spent most of my time standing either in front of the evap cooler (the pad temps were pretty stable at 77) or infront of the exhaust fan trying to dry out a little. The vat temp reached 85.4 and the xenia and rics were in hideout mode. This time the leathers started to react as well, they started to shrivel up a bit and the green was starting to put out quite a bit of a mucus covering. The clam never even flinched though which makes sense as they can spend quite a bit of time in the searing heat out of the water. The discs were curling up some as well and I was starting to think I had reached the ceiling of what they could take. Since the vat was the closest one to the evap I made a wind tunnel out of cardboard to direct the cool air onto the water and waited for 530 to come. Fortunately nothing got worse and after cooling the tanks back down below 84 I was happy things were still doing well.

That night again the fans didn't shut off, and the tank temps were again 79 degrees first thing in the morning. I put the frozen bottles in the tank to cool it down a bit and waited for what Mother Nature would bring today. Apparently the test was over as it was not nearly as bad as the day before. The outside temps still hit 100, and humidity was pretty bad but there was much more cloud cover on Friday and both the greenhouse temps and the vat temps stayed close to what they were on Wednesday. Temps peaked around 2 pm and after that there was a cooler breeze and quite a bit of clouds. Things were starting to cool off and not a bit too soon. The xenia hadn't come out all day, the zo's were not playing peekabo, the kenya tree was still a kenya stump, and only the leathers and clam were looking ok after the onslaught the day before. Forutnately the tank temps topped out at 84.2 and by 11 pm were back down to 81. I had the lights on in the GH as I was making a batch of rock and before I finished up for the night almost everything that was not already gone was back out soaking up the fluourescent glow.

The weekend through today were almost chilly by comparison as temps have been in the low 90's and things have gone very well in comparison with last week. The tank temps still fluctuate quite a bit but it doesn't seem to affect the corals much. The full on sunlight seems to be the biggest issue with most of the corals. That's the good news... the bad news is that starting Wednesday we are supposed to get a couple more days of low 100's but two good things are that it is supposed to be much less humidity, and the temps are cooling more at night this time. That last part is a key as it seems that the tanks are gaining a pretty even amount of heat throughout the day (temp at 6 am vs. temps at 6 pm), and I am guessing this is from the sun as the ambient temps in the gh have been highly variable during this time. It seems as long as the night is cooling them down they do fine in the sun... the nights when they don't cool down all the way seem to bethe ones when there is a problem.

This is very good news, atleast so far, as this means that I can use the tanks as heat sinks in the winter. If these numbers stay consistent, I can let the sunlight heat the water during the day and keep the GH cooler at night. Letting the GH cool down to high 60's at night will make a huge difference in the gas bill vs. having to keep it 76 all day long. I am waiting to hear back from the furnace manufacturer what his estimates are for the difference but I would expect it to be significant on the coldest nights. Also I won't have to worry about heating at all when the sun is out as the tanks should be absorbing enough heat to keep them warm.

All this got me thinking, and I found some huge holes in my logic that this might help with. For one I was thinking that having more gallons in the tank would be creating heat sinks that would help with heating and cooling, but if you try to keep the vats at a certain temperature there is no net heat loss or gain so if I don't allow the tanks to change temperature I lose most of the benefit. I still get the insulating factor of the extra water but I wouldn't get the stored heat. Another is that heating the water and the GH should give huge benefits in energy consumption. If I can use sump heaters to heat the water and allow that heat to radiate off the water surface it is coming off as Infrared heat that way versus convection heat coming from the furnace. The inner layer of poly is designed to reflect infrared heat but will lose convection heat through the many leaks in the surface of the greenhouse. Infrared heat isn't lost as well through a crack since it is heating whatever surface it hits.

**The new idea is to use sump heaters to heat and maintain the water a few degrees above the furnace setting so that it simply kicks in to make up for drafts and really cold nights. Unfortunately I will have to test this out as it starts to get cooler at night, but it seems to make sense with most of the people I have talked to about it.

Anyone have input on it ??

[raaden]

KaptKen,

I am seriously looking into geothermal for when/if I decide to expand the greenhouse. I wrote up some ideas on it back in the BP thread, but for now it was just too expensive to try and do for one gh. I was looking for the geothermal to be used for an HVAC system and the total cost was pretty high compared to what I have now. I think it was in the high $10,000's for a complete system for the size I have but only a few thousand more for one to handle 3 GH's. Since I didn't know how things were going to work out I decided to wait and look back into it when/if I decide to expand.

When I was talking with the GH supplier he put me in contact with some people who had installed goethermal in western NC for greenhouses and they all said that the expense is not worth it for something this small. With our ground temps it would be absolutely perfect as the well water is pretty consistent at about 55 so I am pretty sure it would work well should I go that route.

To use it as a heat exchange medium for the tanks directly is close to what I tried to do with the heat sinks I put in the tanks but i didn't make the run into the tank long enough to get enough temp increase in the line, so I am not sure if I am going to stick with it or not. I might try a longer run in the Poly tank to see what it does though.

[michika]

This is a fantastic thread. Its an amazing build, and I'm really interested to see where you try to take this in terms of research. I wish you luck with your heating problems!