How to set up a RDSB?

[Alieu07]

Last month i had a high nitrate problem, I lost 50% of my SPS. But it been under controled by alot of water change. From 90 ppm to now 10 ppm. Anyway I am learning toward to a RDSB. How do you set up a RDSB in a 5g bucket? It is basiclly put alot of sand to a bucket and water in and out from the bucket. If you have pictures to show that be great. Thanks in advance.

 

BTW my sump have a small section for refugium and alot of sand in there with cheato so not much room for the cheato. So i want to remove the sand to a RDSB.

[hlem]

anh Andy, my is set up with 2-30 gallon tanks. Both are about 6in deep, fine sand, slow flow. it's part of the system. Main tank drain into the first 30 gallon, then skimmer tank, and finally the second 30 gallon tank, which is where the return is as well. not sure if this answer your question tho

 

let me know if you need help setting one up at your place.

[surf&turf]

Last month i had a high nitrate problem, I lost 50% of my SPS. But it been under controled by alot of water change. From 90 ppm to now 10 ppm. Anyway I am learning toward to a RDSB. How do you set up a RDSB in a 5g bucket? It is basiclly put alot of sand to a bucket and water in and out from the bucket. If you have pictures to show that be great. Thanks in advance.

 

BTW my sump have a small section for refugium and alot of sand in there with cheato so not much room for the cheato. So i want to remove the sand to a RDSB.

 

Why don't you try dosing vinegar, or another carbon source?

[Alieu07]

anh Andy, my is set up with 2-30 gallon tanks. Both are about 6in deep, fine sand, slow flow. it's part of the system. Main tank drain into the first 30 gallon, then skimmer tank, and finally the second 30 gallon tank, which is where the return is as well. not sure if this answer your question tho

 

let me know if you need help setting one up at your place.

The wife don't want me to set up more tank So i just want to use a bucket. Thinking to Drill 2 small hole to the bucket near the top and one for drain the other for return(maybe a maxi-jet).

[Alieu07]

Why don't you try dosing vinegar, or another carbon source?

I did look up on line the other day, Dosing vodka and vinegar seem like complicated to me so don't want to risk.

[icecool2]

How big is the DT you want this sandbed for? Are you thinking of using sand or miracle mud?

[Alieu07]

How big is the DT you want this sandbed for? Are you thinking of using sand or miracle mud?

The DT is 180. I am thinking to remove all the sand from the fuge and let the fuge just cheato. Thx

[icecool2]

For a tank that large, you really will get almost no benefit from a 5g bucket. If you had a 30g and used a 5g bucket, maybe. Let's try and find the root of your nutrient problem.

 

How much LR is in your system? How much and how often do you feed? What livestock do you have?

[davelin315]

Andy, I installed a RDSB in my system and it didn't help my nitrates out. Mine was fed by my skimmer to give it cleaner water and the water went in the top and out the side. It's in a 33 gallon rubbermaid brute trash can...

 

The theory behind them is that you run water quickly through them so that detritus does not have time to settle and cause the issues that are normally seen with DSBs. You should filter the water entering them so that they don't introduce any solids.

 

You'll find varying success with them but mine did not have an impact and when I tear down to set my tank up again this summer I'll be taking the RDSB out.

[Alieu07]

So no need to set up a 5g bucket RDSB. I just keep doing 40g of WC weekly. I been thinking the denitrator but can't afford it.

[hlem]

So no need to set up a 5g bucket RDSB. I just keep doing 40g of WC weekly. I been thinking the denitrator but can't afford it.

 

do you know if any larger fish disappeared, maybe something died and that was the cause of your spike...

[icecool2]

So no need to set up a 5g bucket RDSB. I just keep doing 40g of WC weekly. I been thinking the denitrator but can't afford it.

 

My suggestion, no don't setup the 5g bucket. You have a nutrient export problem which is why you are reading high levels of nutrients (nitrates in your case).

 

You have a few options for eliminating them (in order of preference and my no means exhaustive):

1. Biofiltration

2. Mechanical/chemical filtration (carbon, GFO, etc)

3. Strictly water change

 

You really want your tank to be in a natural balance. Hence my original question.... How much LR is in the tank, how much do you feed, how heavily stocked is your tank? Typical reasons this happens is a young tank is overstocked or the tank is overfed.

[Alieu07]

do you know if any larger fish disappeared, maybe something died and that was the cause of your spike...

No fish died. Everybody still there and happy

[Origami]

While the RDSB is a means of biofiltration, Andy, I agree that on your tank, you may not see much from a 5 gallon bucket - there's just not enough surface area across the top of the bucket to give much anaerobic (low oxygen) volume below. Remember, there's a band of anaerobic space below the sand surface, below which the environment begins to lean toward anoxic (absence of oxygen) which is what you don't want because this kind of environments leads to production of hydrogen sulfide. Try carbon dosing and see if you can bring this under control.

[Alieu07]

I have about 100 pounds LR there, it was 200 pounds or so LR in there but I like the open look. I took 100 pounds LR out 2 weeks ago but it been high nitrate.

I feed them once a day+seaweed every other day. I have 25 fish there, 6 tangs and an angel from 4" to 6" the rest of them are small.

 

And I have a BRS dual reactor for carbon and GFO.

 

I been feeding frozen food w/o rinse it with rodi water might be one thing.

 

Does the sulfur denitrator really works?

[icecool2]

I think you are highly overstocked (I tend to be conservative, so others may disagree). How long has your tank been up for? 100 pounds of rock and a minimal sandbed are not going to cut it for a bioload that big. Are you running the GFO reactor?

[Alieu07]

I think you are highly overstocked (I tend to be conservative, so others may disagree). How long has your tank been up for? 100 pounds of rock and a minimal sandbed are not going to cut it for a bioload that big. Are you running the GFO reactor?

The tank been up for 10 months.

Yes I am using the BRS dual reactor for carbon and GFO.

 

Tom, what is carbon dosing and how it works?

[icecool2]

10 months? Yikes. Your tank isn't ready for the bioload you put in it and then you removed half of the biofiltration from the tank. If you are running carbon GFO you are already dosing carbon. I don't mean to be a wrasse here, but you need to cut back the number of fish you have and get your tank in order. Carbon and GFO are great when used properly, but you need to practice proper husbandry first. Anything you do at this point is just going to be a bandaid until you get your bioload to the proper level. Carbon dosing only supports the bacteria in your system. 100lbs of LR with 25 fish is unsustainable without extreme intervention on your part.

 

Nutrient import needs to match nutrient export or you will be constantly fighting this problem.

[Origami]

...I took 100 pounds LR out 2 weeks ago but it been high nitrate.

Andy, this may be at the heart of your problem. By taking out a 100# of rock two weeks ago, you've decreased your biofiltration by nearly 50%. Your remaining rock may be able to catch up, but you've got a lot of fish that makes up for a large bioload. It may or may not catch up. GFO can help reduce phosphate, but it will do nothing for nitrate. It may, in fact, limit the uptake of nitrate if you're too phosphate limited. (I doubt that's the case, though, because you must be feeding heavily to sustain this many fish).

 

Do you have any room to put that 100# of rock back in? Maybe a sump?

 

Watch your nitrate levels. If they continue to creep up at the same rate, without backing off, you're either going to have to increase your filtration or decrease your bioload. Water changes to manage nitrate, by the way, will lead to quicker depletion of alkalinity relative to calcium. The end effect is that you'll have to dose alkalinity to maintain balance.

 

You might be able to use a denitrator coil or sulfur denitrator, but I don't know how much coil would be required to replace 100# of rock. I've never seen a guideline for this.

 

Carbon dosing can increase the bacteria in your system. Effectively, what you're doing is you're providing more low-nitrogen food for them. This can increase numbers, raising the uptake of carbon, nitrates, and phosphates. If you don't have enough anaerobic surface, though, for bacteria to colonize, this could become the limiting factor.

[Alieu07]

Andy, this may be at the heart of your problem. By taking out a 100# of rock two weeks ago, you've decreased your biofiltration by nearly 50%. Your remaining rock may be able to catch up, but you've got a lot of fish that makes up for a large bioload. It may or may not catch up. GFO can help reduce phosphate, but it will do nothing for nitrate. It may, in fact, limit the uptake of nitrate if you're too phosphate limited. (I doubt that's the case, though, because you must be feeding heavily to sustain this many fish).

 

Do you have any room to put that 100# of rock back in? Maybe a sump?

 

Watch your nitrate levels. If they continue to creep up at the same rate, without backing off, you're either going to have to increase your filtration or decrease your bioload. Water changes to manage nitrate, by the way, will lead to quicker depletion of alkalinity relative to calcium. The end effect is that you'll have to dose alkalinity to maintain balance.

 

You might be able to use a denitrator coil or sulfur denitrator, but I don't know how much coil would be required to replace 100# of rock. I've never seen a guideline for this.

 

Carbon dosing can increase the bacteria in your system. Effectively, what you're doing is you're providing more low-nitrogen food for them. This can increase numbers, raising the uptake of carbon, nitrates, and phosphates. If you don't have enough anaerobic surface, though, for bacteria to colonize, this could become the limiting factor.

I sold the rocks also no room in the sump.

[Origami]

BTW, there's a difference between carbon GAC, which is inorganic carbon, and carbon dosing, which is dosing organic carbon. One is bio-available for heterotrophic bacteria and the other is not.

 

A few years ago, there was a really long thread over at RC that went over the trials of Vodka dosing for many, many reefers that gave it a try. In 2008, this article was written to summarize a compromise protocol:

 

http://reefkeeping.com/issues/2008-08/nftt/index.php

 

Other forms of dosing have since evolved. VSV (Vodka Sugar Vinegar) dosing, as well as solid-vodka (aka biopellets), have been part of that evolution.

 

On my old 90, I tried all three, although separately and, instead of glucose as the sugar, used regular table sugar. They do work, although I think I may have seen more browning of corals with table sugar, and better color with vodka. Not sure, off hand, of why that would be.