DSB in a bucket for nitrate control

[jrandreassen]

I'll let you know how mine goes...
I'm putting in a 6 1/2"W x 9"D x 90"L uder the fuge this week-end.
My NO2 is pretty high(40) right now, so I'm hoping it will make a substantial difference.

Question for the Guru's:
Should I seed the sand with some pure carbon ??
If so, how much ??
JR

[tonym10]

10 month update
Here is an old pic of my rdsb, set up to 10 months ago. My nitrates were hanging around 40ppm. After doing lots of water changes back then to drop them to 2ppm they were on the rise back up. So I tried the rdsb. Now 10 months later nitrates are undectible.

[the other tang]

Not sure i'm an expert by any means but i am seeding mine, i am building it now. Just a few more fttins' and I'm there. I also seeded mine with sand from my display, i attempted to siphon mainly from the bottom of the 4" bed in hopes of getting some useful bacteria. I think that might kick start this thing, but as always time will tell. The downside seems nil, I have dosed sugar for some time with no issues and sand from my system into the rdsb seems logical as well.

[the other tang]

I just fired up my rdsb, I am using a 5g water container" which i highly recommend over a bucket" driven by a mj 1200. I am using 3/4" into the side and a 1" return out the top. My problem is I am getting a ton of air from my skimmer output into my mj. I have a hob styly skimmer with a 1 1/2" pvc output with an elbow on the end, i have my mj laying sideways with the intake actually sitting inside the skimmer return. I could easily move it out of the bubble filled skimmer stream but that would be defeating the purpose, right? Is this a real problem? The air would go in and move across the top toward the return never really getting near the sand. I'd love to get some opinions on this, thanks in advance.
Rusty

[BeltwayBandit]

I was perusing this thread (I read a lot of it but not all and did some searching for the rest). I saw where Anthony said that planting Mangroves in an RDSB would be OK. My question is what about shoal grass, Halodule wrightii, or similar. The reason I ask is I came across these grasses in an article on Nitrate in Advanced Aquarist. The article suggested that these grasses grow faster in environments with elevated nitrates, where other plants' and corals' growth may be stunted by such levels.

Now consider, most people consider using an RDSB when they are having nitrate issues. Would it increase the effectiveness of this setup to include a plant that also thrives in a high nitrate (relatively speaking) enironment to help reduce the levels? Or, possibly even allow for a larger tank volume to be handled by a smaller bucket? i.e. instead of a 5 gallon maxing out around 100 gallons, would the inclusion of sea grass increase the effective loading appreciably?

[TekCat]

Growing grasses require their periodic prunning to export nutrients. IMHO, this would be best done in a fuge. And RDSB is plug'n'forget thing: set it up and never touch it for 2 years.

[mr.wilson]

As TekCaT suggests, a DSB is affordable, "set it and forget it" technology. On the down side, they appear to require about a year to generate a stable population of pseudomonas to reduce nitrate. On the plus side, once the nitrate is reduced and a balance is established, the bacterial colony is capable of dieing back to a suitable size to govern the nitrate food source (a self regulating system).

Sea grasses are a great addition to your system, but they are to be treated as a separate entity with their own pros & cons. They can be high maintenance as they require harvesting, may need nitrate supplementation once they reduce existing nitrate, they require high intensity lighting that can cause over-heating and energy consumption, and they are very difficult to transplant successfully.

With patience a DSB may be all you need for nitrate reduction, but any other method certainly helps, especially one that can offer pro-botics and aesthetics.

[a4twenty]

on top of that wouldn't you need light for the sea grass to grow? i think it is very important to keep light out of your RDSB to avoid algae growth. since i've added my RDSB ( almost a year now ) i don't have to trim my macro. it doesn't grow very much at all any more, i'm actually worried it may just die.

[Smokie 1118]

WATER OVERFLOW!!!! I was so excited to try this. I have a killer skimmer but for some reason my nitrates are at 50 and I cannot get them any lower. So today I plumbed a 1/2" ID flexible hose to two 1" PVC pipes. The 1" PVC went into the bucket and it was reduced to 1/2" flexible pipe for both the water pump line and overflow line. Everything ran smoothly for two hours and then there was so much air in the drain pipe that the water stopped draining. However the pump kept pumping. Need less to say I had quit the mess. Anyone else have this problem and how do you get air out of the drain pipe?

[Safedad]

I just got mine started. I used a 5 gal Ocean Salt bucket and used uniseals. The 1" infeed and discharge are at 12 n and 2 pm (looking down on top). Both have a 90 degree elbow so the water flows around the top and out the discharge. I thought this might give a little more residence time. I have 2" very fine sand at the bottom and 6" of Lowe's sand above that and 2" crushed coral to keep it in place. I had a devil of a time getting the top to seal. Used Oatey teflon paste. My starting Nitrates are 40 (down from 80 with water changes and nitrasorb). My bucket is in a closed loop following a torpedo filter with carbon and right now bacteria and a flow rate of about 550gph. I have a 55g with 3" maroon (two GBT anemones as best friends), 2 perculas, 4" regal tang, 2.5" coral beauty angel, and 2 blue green chromis. I am just starting to add corals so Coral Beauty Angel might be moving on. I will track the nitrates and let you know my decline rate.
Thanks for the inspiration,
Bob

[Pmolan]

I skimmed through almost the entire thread... I have 2 giant megaflows on my tank, the bottom 18" is water. Can I fill these with sand and get the same results? Seems like useless space anyway.

[Smokie 1118]

Fixed my overflow......Put at 1" PVC with a 1" ID large flexible tube....Have a larger overflow than the infeed!!!

[Malifluous]

For those of you that have taken down the RDSB, Did u find any bad smell or detritus accumulation iside it?

[dstalfire]

Can anyone running the RDSB please post your before and after nitrate readings?

[the other tang]

RDSB update, DO NOT USE a 5g blue water jug from walmart. They simply can't handle the pressure. It bulged as soon as I fired it up and I assumed the round "ish" shape would help it to hold. WRONG, it started leaking on Thursday so it lived some 16 days. The good thing about this experiment is I can definatelty say it was showing signs of working. I know it was not fully seeded in that short time, but the fact that I seeded it throughout with ls from the deepest part of my bed had some impact. In those 2 weeks, i went from showing 30ppm nitrate down to 10ppm. I kept the same schedule on waterchanges and changed nothing else. I will now plan my next container. Any ideas? I have to believe I would get the same pressure issue with a 5g bucket. I believe the flat bottom and lid would be the weak link, right?

[BeltwayBandit]

"As TekCaT suggests, a DSB is affordable, "set it and forget it" technology."

While I agree that the basic RDSB is set it and forget it, space is at a premium for me. If I am alocating space to something and I can get multiple uses from it then why not try it? My question was more along the lines of how can you maximize the use of an RDSB type of setup. Our reef club just had Barry from clamsdirect come speak over the weekend and now I am thinking about possibly using some hippopus clams as well in the RDSB. (again lighting isn't an issue since I converted a 'fuge in a bucket' to a RDSB so I already have a light (19w PC floodlight) and two mangroves in there).

The hippopus clams require very little light and appear to be among the better denitrators among the giant clams (anecdotaly, I don't know of any solid reference for this).

So far I have identified three things that I am looking to try in my RDSB Mangroves (has been done before), seagrass, and hipoppus clams. I'll be curious to see the results.

[the other tang]

BB, please post the results. I am curious too. I assume you read the thread, something I am looking to add to the next evolution is argronite. The low ph in the bottom of the rdsb will be able to dissolve the argronite which is a big deal for me, I don't run a ractor and like you wast them most from any space I allocate to. Any one have suggestions of a good container for a hob style loop? The pressure killed my last"see above" experiment.

[mr.wilson]

Originally posted by the other tang
BB, please post the results. I am curious too. I assume you read the thread, something I am looking to add to the next evolution is argonite. The low ph in the bottom of the rdsb will be able to dissolve the argronite which is a big deal for me, I don't run a ractor and like you wast them most from any space I allocate to. Any one have suggestions of a good container for a hob style loop? The pressure killed my last"see above" experiment.

Localized acidity in the substrate has only a nominal impact on buffering PH up. If you have a high demand for calcium & carbonates this will be too little, too late.

Calcium reactors deliver a PH of 6.5 over a great area with a flow through for maximum exposure. The dissolution rate in a calcium reactor is about 50% of the media per year. The dissolution rate of media in a DSB is about 5% per year.

The bacteria that reduces ammonia develops in weeks, the bacteria that reduces nitrite takes months, but the bacteria that reduces nitrate takes about a year to grow to a formidable colony. Your reduction in nitrate is likely due to the detritus you removed with the sand when you set-up the Walmart container.

[BeltwayBandit]

Originally posted by the other tang
BB, please post the results. I am curious too. I assume you read the thread, something I am looking to add to the next evolution is argronite. The low ph in the bottom of the rdsb will be able to dissolve the argronite which is a big deal for me, I don't run a ractor and like you wast them most from any space I allocate to. Any one have suggestions of a good container for a hob style loop? The pressure killed my last"see above" experiment.

Ok.. well I guess a good place to start is at the beginning. I used 60lbs of oolitic aragonite sand (caribsea to be exact) in an old 200gal IO salt bucket. I have 2 mangroves planted in the sand and the setup is lighted by a 19w PC floodlight (don't remember the manufacturer but got the lead from Melev's site). Currently Nitrates are between 5-10 PPM (running 5 days no change) with an old (3+ years) Salifert test kit. I will be getting a newer kit in the near future and will update the results accordingly. I am waffling on ordering seagrass right now due to being the wrong season for collection (seahorse.org had a post recommending against buying seagrasses in the wintertime since most are wild harvested in Florida). Plus of a more practical nature, will be purchasing as a part of a group buy with my local reef club and many other items at the online vendor are also out of stock due to the season. I will post test info as I get it, and will update with stocking info on my RDSB/denitrator combinations as I work through them.

BB

[teggs]

Wow ... 50 pages!

I'm actually a FW fishkeeper and never had a marine tank (one day though) ...

I already have 2 coil denitrators on my 200G monster tank and I want to try a RDSB due to my extreme bioload. I have everything ready and will be "plugging it in" tonight.

Thanks to Captain Calfo and all the other enthusiasts that made this thread and RC the bext place for marine info in the world..

Andrew

[TekCat]

Silica sand could be used instead of aragonite if one worries about aragonate disolution.

[mr.wilson]

Originally posted by TekCat
Silica sand could be used instead of aragonite if one worries about aragonate disolution.

Good point. Non-calcarious media has the benefit of never turning into concrete slabs. Glass beads as used for sand blasting may be another viable altenative.

[the other tang]

I do not have a huge calcium demand as many others on here do, I really only have to dose a bit of calcium at waterchanges and all is well. I use a small ammount of kalk too and thats it. I will take the 5% as a plus in my situation, I have no need for a reactor at this point. If these things truly have a two year life span, then let it solidify in my case it doesn't matter. It will be coming out in two years anyway.

Mr Wilson, I have to believe between the seeding and sugar dosing something as happening.I fully agree that it was far from a mature colony. I failed to report in my post that my nitrates shot back up almost instantly when I took the rsdb offline. No other changes were made. When i siphoned the sand out of my display for seeding I got one spot that was piled up in the front corner "approx 2-4 lbsof sand"and never moved the tube, providing I had a deterius problem it seems that amount being removed would have little impact. I put it in layers as I was filling the container with silica, as well as a total of 1/2 tbsp of sugar.

[RichConley]

Originally posted by the other tang
RDSB update, DO NOT USE a 5g blue water jug from walmart. They simply can't handle the pressure. It bulged as soon as I fired it up and I assumed the round "ish" shape would help it to hold. WRONG, it started leaking on Thursday so it lived some 16 days. The good thing about this experiment is I can definatelty say it was showing signs of working. I know it was not fully seeded in that short time, but the fact that I seeded it throughout with ls from the deepest part of my bed had some impact. In those 2 weeks, i went from showing 30ppm nitrate down to 10ppm. I kept the same schedule on waterchanges and changed nothing else. I will now plan my next container. Any ideas? I have to believe I would get the same pressure issue with a 5g bucket. I believe the flat bottom and lid would be the weak link, right?

How are you setting yours up? There really shouldnt be any pressure?

[the other tang]

The head X the area will give you quite a bit, the jug was tight as a drum once filled. I don't have a pressure calculator anymore but someone took the time to do the long math back oh 20 pages or so, and it was allot more than you'd think. I can't remember the exact # but it was pretty high.

I set up a simple loop, mj1200 out of display to rdsb via 3/4" tubing, returning in 1". There was no restriction other than the unavoidable ones, such as the container itself. I will start on 5g bucket tonight, using the good old style IO salt buckets with the ratcheting gasket sealed lid, before they went to cheap lids.