Large Tank IN a Basement-Ventilation Suggestoin Please oh brethern of the mamoth tank

[Chris Witort]

1/2" is rated for 12" spans, 5/8" is rated for 16" spans. If you have anything wider you would need to use standard 5/8" drywall or celing board. It will tend to sag slowly otherwise.

[skippyreef]

Thanks for the informtion. We read a lot before we purchased anything and everything is 16" on center as far as apans

[capncapo]

bstone,

A little more info please .......

Your fish room is the deep area of the garage.

How about an approxmate size. Hopefully it is insluated .... both the walls and ceiling?

Your furnace and A-coil are in the other area of your garage.

Is that area insulated also?

What will your total water volume be? Include tank and any sumps, refugiums, etc.

What is your ductwork made of and is it insulated?

Why do you think you want to bring outside air into the fish room and then vent your fish room air into your garage?

Any other info that you may think important?

Got any pictures?

Thanks

[Gudwyn]

"HRVs are great but have a limited season as they are for use in cool/cold weather."

HRV's will reduce humidity in an area with a large reef tank in most weather.

The one case where they don't work is when you are using AC in an area with high outside humidity (gulf coast for instance). In that case, the AC reduces the indoor humidity and an HRV just sucks humidity back into the house. But if you aren't running the AC, running an HRV in your fish room almost always helps.

As far as the question about sub-zero, yeah they work fine. Canada requires HRVs in all new construction.

[bstone]

bstone,

A little more info please .......

Your fish room is the deep area of the garage.

Yes, the garage on the left side is 2 deep. I converted that area to a fish room. It is completely closed off from the garage now.

How about an approxmate size. Hopefully it is insluated .... both the walls and ceiling?

18'-6"x11' ceilings are 9'. Yes, everything is insulated, ceiling and walls.

Your furnace and A-coil are in the other area of your garage.

Yes

Is that area insulated also?

Garage is insolated except for one side, and garage doors.

What will your total water volume be? Include tank and any sumps, refugiums, etc.

1000 gallons

What is your ductwork made of and is it insulated?

Not metal, its the plastic insolated type.

Why do you think you want to bring outside air into the fish room and then vent your fish room air into your garage?

No idea, that is why I need you assistance!

Any other info that you may think important?

I have a window AC unit in my fish room the vents out into the garage. I do have a dehumidifier, if needed.

I will have pictures soon!!

Thanks for your help! Also, sorry for hijacking this thread!!

[capncapo]

bstone,

One more thing ........ what about heat for the fish room? Do you have that taken care of already?

[bstone]

Do you mean during the winter time? I am thinking the 2910 watts of lighting will keep the room warm. I have about 900 watts during the night time over my refugium and coral prop tank.

[capncapo]

And how about the floor in the fish room? Just concrete or have you done something else with it?

[Nataku]

First, I want to say this is a great thread.

I came to the same conclusion as skippyreef at least in theory . Summer time i would run a fan into the cold air return kind of like a 1st stage forced induction. Then in the fall and spring when the ventilation is not running to vent outside.

Perhaps there's a way to run both fans on the house thermostat. When the vent is running the fan on cold return will run. When the vent is off have the outside fan to run. that way humidity is constantly removed. In both cases i would run a low volume fan not to draw in too much outside air.

As well, I was thinking about protection for the exposed wood in the basement. Perhaps apply some type of wood sealer such as Thomson's water seal or polyurethane. I could use one of those airpumped sprayer for weedkiller / insecticide instead of painting it on.

[bstone]

And how about the floor in the fish room? Just concrete or have you done something else with it?

It is just concrete.

[skippyreef]

my fan will exhaust the room in something like 2 minutes. According to the calculations I did I could have gone with a 75 CFM fan to get 8 air exchanges an hour but I did not want the fan running all the time. I think it is best to get the humidity out in a timely manner

I also used the green board to cover up the ceiling and seal in the wood so that there will be minimal opportunity for the wood to act as a sponge for the moisture.

I think that by keeping the basement temp around 68 degrees that the tank will not evaporate at the same rate as it would if the temp was say 75. The cold air returns will also aidde in preventing any problems I think.

[capncapo]

bstone,

A few points for you.....

Were I going to do what you are about to do, I would first do something with the concrete floor. You could quite possibly find that it will influence the temperature in your fish room as much ( if not more ) as any other factor.

I'm also assuming that the door into the fish room is located in the garage? If that is the case, that will be another source of undesirable air infiltration that wiill also influence the temperature of the room.

What I'm trying to get at is that it's tough enough to control room temperatures in a fish room when there are very few, if any, external sources of heat or cold but to try to control them with a slab of concrete that only partially contained in a treated space and an entry door that opens to the same could prove to be a frustrating experience that would best be avoided. Personally, I would put in a raised, insulated floor and use an exterrior rated door.

You aren't that far away from where I live so I'm sure that you have those 0 degree days in winter. Your main lights should be plenty duuring the day but I'm not so sure about your other light being all that's needed on those cold nights

I would also consider adding some type of auxillary heat source just in case your lights don't give enough heat during a long cold snap. Your main lights should be plenty during the day but I'm not so sure about your other lights being all that's needed on those cold nights and it doesn't hurt to have a backup system just in case.

Now, on to the particulars ..........

You are going to have a buttload ( a scientific heatng and coolng term that means A BUNCH ) of water contaned in a relatively small area. On top of that, you will be using lights that will create loads of heat so you are going to need to become very aggressive in your methods of controlling both the humdty AND the heat.

You will need to use both your window A/C and dehumidifiier. The vapor barrier you asked about should not be needed.

In addition to that, I would use some type of vent fan that is vented to the outside ( not the garage ) for use when the temperatures and humidity levels outdoors are acceptable enough as to allow for its use. You can't use them all of the time but when you can, using them instead of the A/C and/or dehumidifier can save you some good money; enough to pay for the vent many times over. Remember that if you add any kind of fan that vents air out of the house that you must have a way for outside air to come into the house.

I don't know whether you use gas or electric heating but most homes that use gas heat could stand some additional humidity in winter. I will assume that you have gas heat and with that in mind, there are a couple of ways for you to incorporate your fish room into your home heating and A/C system.

My preferred method would be to run some ducts ( supply AND return ) from your furnace unit located in the garage to the fish room. I would locate the return duct near the ceiling and the supply duct near the floor. If you connect the ducts to closeable registers, you can regulate just how much air goes through your heatng/cooling system and can also close them which would effectvely remove them from the system.

The second method would be to add some vents that penetrate the into the fish room from the wall that is common with your famly room. I would use at least a total of 4 closeable vents and would place 2 of them high up on the wall and the other 2 would be placed near the floor. Doing this will allow air to circulate from the fish room into the house both helping with temperatures and humidity and the best thing of all is that it would be strictly a passive system in that no fan would be requred to produce that circulation. With closeable vents the system could effectively be turned off and on simply by closng or opening the vents.

You might consider doing both of the methods mentioned above. I would do both as I would much rather have and not need than need and not have and now, while construction is going on, is the time to make changes.

Doing this will allow your home heating and cooling systems to help with the task of keeping the fish room environment within an acceptable range.

When it comes to very large tanks/water volumes and lots of MH lighting, much of the temperature and humidity control is a fly by the seat of your pants type of thing as every setup is unique and, as such, unpredictable. I would install as many contingencies as possible while constructing the fish room rather than go through the pain of tryng to add them after the tank is up and running. With serveral methods of control you will have the ability to "tune" the systems for optimal performance in every season.

Good luck!

[bstone]

capncapo

Thanks for the detailed description on how to control thew temp./humidity in my room. When looking at my fish room in relation to my furnace, it would be very easy to add a supply and return to the fish room. Also, adding closeable vents to the wall between the fish room and family room is also very easy. None of my drywall or insulation is up right now, so it would be very easy. Adding a fan that vents are from the fish room to the outside might be a little harder, but doable! The exterior of my house is brick, so I would have to cut through that.

What do you recommend as a sequence of events to do, lets say in the winter time to the summer time. Such as in the summer time open the vents from the fish room to the family room, then open vents for supply and return to AC if humidity and temp are still high, then turn on fan to vent out air to outside, then us window AC and dehumidifier?? Something like that, and then a different sequence for winter?

Thanks again, these are all great suggestions that I will implement soon!!

[capncapo]

bstone,

That is a question that would probably best be answered by you after studying the effects of each of the various methods on both your fish room and your house. Each of the methods will have a different "degree" of dehumidification and heat control that can only be determined after all of the systems are in place and put to use.

A couple of the methods ( vents in the walls and connecting ducts to your heating and coolng system ) will have an effect on not only the fish room but your home as well. Whether it will become noticeable to you or not depends on how much heat and humidity will be generated and brought into your home and how well your heating and cooling systems are functioning.

The use of a vent to the outside should only be used when outside humidity and temperature levels are within an acceptable range. Depending on how much heat your lights produce and the humdity level of the fish room, acceptable levels could be only on cool dry spring and fall days and nights or could possibly even include winter days. You'll have to experiment and figure out for yourself when to use the vent fan. I would try to use it as much as possible as it will be the least costly to operate of all the active components. Needless to say, you won't be using it much, if at all, during the summer months for sure

I wish I could give you a hard and fast answer on when to use what but to even attempt that could end up making a fool of me and making you mad or even worse. The best I can do is to tell you to study everything you can about how the various systems impact the heat, humidity and even other systems and then put into practice what you learn. Don't be afraid to experiment with different combinations of systems in different weather conditions and make sure that you document your findings for future reference.

Personally, I would try to use the systems that cost the least to run as much as possible and use the others only when needed.

Don't forget that dehumidifiers produce a fair amount of heat and that using the air conditioner in your home to cool the fish room will probably cost less than usng the window A/C unit ( depending on the efficiency rating of your home A/C ).

Good luck and post some pictures so that we can see your setup and your progress.

[bstone]

capncapo

Thanks for all your help! I needed this type of help when it came to humidity/temp control. I will end up doing everything except the sub floor. My stand is already built, so there is no way to get a sub floor up now! Thanks again for your help! Here is a link to my project w/ pictures.

http://archive.reefcentral.com/forum...5&pagenumber=1

[bstone]

capncapo

I bought a exhaust fan for the room. I think its the same one listed on this thread. I am looking at controllers, do I want one that turns the fan on when just humidity is above the setpoint, or when temp and/or humidity is above the setpoint?

I can get a dual controller that turns the fan on when above the setpoint on the humidity, and then turns on the window AC unit when temp. is above setpoint. Remember, the window AC unit will be my last resort if my house HVAC unit can not cool the room enough. I kind of like the idea of setting up a controller that would have a dual output independent for both humidity and temp.. What are your thoughts, what would you use in this setup?

Thanks.

[capncapo]

bstone,

It would be nice to control the fan in an and/or fashion but I'm not familiar with a single device that will do that. You could wire a humidistat and thermostat in parallel to accomplish that. You might also need to add a diode or some other component to each to keep electric from "backing up" into a unit while it is off but the other is on.

That being said, a lot depends on the temperature and humidity level of the outdoor source air. It's a given that the exhaust air will be hot and/or humid but what about the air coming in? If it's hot or humid, you don't even want to use the fan.

I think I would also put a on/off switch on the exhaust fan AFTER the controls so that you can shut it off should outdoor conditions be less than desireable for its use. That would allow any controls attached to function normally but the fan would not be activated.

Personally, I would not use a combination device. I would use standalone devices. To use a combination device creates a situation where a single point of failure is possible. I would try to avoid that at any cost.

Something for you to remember when you are looking at purchasing these controls is that you will be looking at "line volt" devices. Most "normal" thermostats and humidistats use 24v that energizes a contactor ( relay ) that then switches a higher voltage on and off. Line volt devices are powered by 110v/120v and switch the voltages on and off themselves without having to go through a contactor.

Make sure that you get a heavy duty unit for the A/C. The fan won't draw heavy amperage so a normal unit should do fine for it.

[skippyreef]

In the summer months your better of with the A/C unit becaue of the hot/humid air outside. My plan is to install a split A/C unit in the spring seperate from my houses main A/C.

[bstone]

capncapo

This is what I was thinking about, take a look at the CT-DH-2 model. Or I can get two controllers, each separate - one for humidity to control the exhaust fan, and one for just temp to control the AC. Just curious if you had seen these controllers!

http://homeharvest.com/climatecontro...dehumidify.htm

[capncapo]

bstone,

I have not seen those controllers before. The specs look like they would do the job for you provided that your A/C doesn't draw more than 15 amps. According to the info even that can be changed so I don't see why it shouldn't do what you want.

Something you haven't mentioned is your dehumidifier. If I were you, I would have the fan come on first, the dehumidifier next, and then the A/C which means you would need three controllers.

Again, it's just my preference but I would go with discrete devices just to eliminate the single point of failure. What can I say ........ there are some things that I can be anal about.

[Dag]

Capncapco,

My problem is not the winter, it's the summer. My A/C can't seem to keep the house cool. I've had three different HVAC companies examine my system, and all pronounced it fine, including the temperature of the air coming out of the registers.

It's a two-story house (about 3800 square feet above ground) and a basement. I have my 200 gallon display on the first floor, and sump, refugium, etc (about 120 g) in the basement. The tank is kept at 80 degrees, and there are three 250W metal halides above the tank.

There is a 4 ton unit on the first floor and a 1.5 ton system cools the second floor. Second floor is fine. First floor never gets cool enough. (Some might say that the 4 ton on the 1st floor is oversized, but when I changed the unit about 4 years ago, a 3 ton was initially put in, and when it didn't cool, I thought the problem was the size so I upgraded to 4 ton.)

I use a humidifier in the basement during the summer, and I keep the basement doors closed. Also, I changed all my recessed cans in the first floor ceiling to compact fluorescents.

Any advice would be appreciated.

[capncapo]

Aryeh,

There are too many factors coming into play to mention in order to give you the "right" answer. The biggest one being that I haven't seen your house.

A couple of things come to mind. Some are questions and others are comments.

How long does your unit run on a hot day?
When you had the condenser unit ( outdoor unit ) upgraded, was anything else done?
Do you have ceiling fans?

Something to consider is that the humid air will "feel" warmer and you will need to set your thermostat lower to compensate.

Even though you keep your basement door closed when running the dehumidifier, they create a tON of heat and that heat has nowhere to go but up. It WILL make it upstairs.

Reply to my questions and we'll go from there.

[nonot8946]

Has anyone tried simple passive thermal regulation?

Basically seal the tank off from rest of the house (not even the room but just the tank itself). (Most people's hoods almost do this already.) Have one vent that could allow you to pull in cool air leading down. Have another vent leading upwards (hot air rises) to a nearby exit to the outside?

You could put a fan in there for when you need more cooling/dehumidfying.

Provided the vent isn't too far away, seems like you could get decent air movement.

Since the more or less enclosed environment is small, it could heat up quicker, but it could also cool off quicker. Heat rising can draw in cooler air from near the basement floor.

However, since humid air is more dense, would it sink? Then this might not work, so you'd vent the high and low vents outside and have a middle vent with the fan to draw in the cool dry air.

Would the humidity be a problem? Well, I wonder because the hood and lights are basically right off the waters surface so they're pretty much exposed to really high humidity anyways, and everything else is ductwork. When you do expel the humid air, the volume is much less than say, the entire room, so the amount of cold air drawn in from outside is much less, so you have much less of an additional load on the furnace. If you want to warm the air passively, have a seperate vent to the outside that uses a solar heater (basically something black that the sun hits). The sun (during the day at least) can prewarm the air about 40 degrees.

Cost: some ductwork, and a bathroom fan. Even the cost to run the fan has to be cheaper than the thousands of dollars you are all planning to spend on the HVAC and heat exchangers.

The problems are for you guys who live where its hot and humid outside. Then you basically have to rely on your homes AC and dehumidfication because you are replacing hot humid air from the tank with hot humid air from the outside. Maybe geothermal cooling might help a little.

Just some ideas to toss around.

[Dag]

How long does your unit run on a hot day?

On a hot day it seems to run all the time.

When you had the condenser unit ( outdoor unit ) upgraded, was anything else done?

The furnace was also changed. The old furnace was the original unit from the 50's. I was expecting the A/C to work much better since the old furnace had a blower that was never designed to work with A/C.

No other changes.

Do you have ceiling fans?

Yes.

Something to consider is that the humid air will "feel" warmer and you will need to set your thermostat lower to compensate

On a summer day, it is difficult for the reach lower than 71 degrees, and on days when my wife is cooking and using the oven, impossible, and the temperature is usually about 74-76 inside.

Other things I tried in the summer: I covered the tank upstairs, but it wasn't airtight. I also turned off the fans to reduce evaporation. At one point I also reduced the speed of the fan blower.

Everyone says the tank shouldn't be the problem, but I know those lights put out alot of heat, and big tub of water at 80 degrees also creates heat.

I realize there are other factors such a window exposure, but it seems odd that my 2nd floor is fine, and with such a big unit on the first floor (4 tons) it can't cool it down.

Thanks for asking.

[capncapo]

If the unit size was increased and the ductwork was not changed, you may be limited by the size of the ductwork. If the ductwork isnt properly sized for the unit you won't be able to move enough air to keep the place cool.

Something that raises a question in my mind is how can your upstairs remain cool when all of the heat should be going up the staircase? Unless you have a door or someting else between the two levels it doesn't make sense as the cool air from the upstairs unit should be coming down the stairs as the hot air goes up.

I can understand the problem of it not being able to overcome the heat with the oven in use. That is fairly normal.