DSB...Let's Discuss!

[NaH2O]

I love this site for the ability to have discussions on topics that can tend to be "heated". There is a great thread on Jaubert Plenum that has some wonderful information....it's lengthy, but worth reading. Anyway, I plan on having a Deep Sand Bed (DSB) in my tank, and understand there are some cons that go along with this system. What I'm looking for is a discussion on how to make this system work. It has been argued that DSB's only work for a few years, then begin to leach phosphates back into the system....it is argued by others that this system maintains itself, and can last many years. There are many quotes I can pull over from the thread on the Jaubert Plenum, but I don't want to make the initial post of this topic very long.

Tell me, what can I do to make my DSB last? If you have a DSB, what are your experiences, what is your maintenance, and how long has your system been running with a DSB? What are your feelings about stirring the top of the DSB?

Understanding the downfalls of this system may help to make changes in order to keep it healthy.

This is just a start...feel free to quote any comments on DSB from the plenum thread mentioned above.

 

[captivereefs]

My DSB has been in place for 5 years. I do nothing to it. I add no new criitters or sand and it is doing a super job. I have so much life in it that the sand bed itself is fun to look at. I have never stirred it up. I do feed pretty heavy so the micro fauna always have a food source.

 

[NaH2O]

One of my concerns is the accumulation of things such as: byproducts of reactions, end product detritus, absorbed elements, etc. that seem to not have anywhere to go. Are the organisms in the sand bed so diverse that these accumulations will not ever build up to a point of stalling the sand bed?

Captivereefs...I think that's great....do you also have a refugium, or run a skimmer?

 

[fidojoe]

About 2 1/2 months ago, I dumped another 1.5" of sand ontop of my old 1" SB (not the smartest idea to just dump new, dry sand ontop, but the only adverse affect was a partially cyano covered SB) So, now I'm at 2.5-3" of sand at the highest point.

So far, from what I've seen it do, I like it. Before I made it deeper, my nitrates were at a solid 25, then I deepened it, had a cyano outbreak, tested for nitrates a week and a half ago, nitrates were at ~15, tested yesterday and they are about 10-12, and I've only done 2-5 gallon water changes this month (I was supposed to be switching to a 5 gallon WC every weekend, but I tend to forget), when I normally do 2-10 gallon WC's.

As for the "timebomb" thing, I'm not going to concern myself until it is at least 2 or 3 years old, and by then, I'll probably have a bigger tank, and have this one totally redone already.

I don't think that this whole DSB thing should scare people that haven't had their tanks up long enough to even have these problems yet. I also don't think that everyone should go ripping out their dsb's, just because someones tank crashed and the DSB played a role in that happening.

 

[NaH2O]

Originally posted by fidojoe

As for the "timebomb" thing, I'm not going to concern myself until it is at least 2 or 3 years old, and by then, I'll probably have a bigger tank, and have this one totally redone already.

...me too....I'll always upgrade....eventually I'll be the one in the glass or acrylic box...lol

I don't think that this whole DSB thing should scare people that haven't had their tanks up long enough to even have these problems yet. I also don't think that everyone should go ripping out their dsb's, just because someones tank crashed and the DSB played a role in that happening.

I agree...I do feel it is important for people to understand how the sand bed functions in order to benefit from it the most.

 

[RogueCorps]

Mikey...

This one's been eating at me for a long time so tonight I finally took it upon myself to see exactly what's in there. So I pulled out the microscope and saw this!

Geez... how could I be so wrong. You were right Mike!

 

[Maxx]

LOL RC......
Someones got tooooooo much time of his hands....
Nick

 

[NaH2O]

OMG...Rogue, you better hurry up and rip out that ticking time bomb! Maybe the sand bed has special forces that will defuse those, little Boomers, if you will. What happens when the critters eat that stuff? Will other critters eat the exploded critters? I think I should do a study.....

 

[Scooterman]

Before we go into a DSB discussion & this goes to all, regardless of how long you've had one in operation, would you post your DSB set-up, tank critters & inhabitants & a little more detailed information on Exactly what do you do for cleaning or up keep. I think we need to start off of fair grounds before going into a discussion. If you change water, do you vacuum, how big are your fish & how much it lots of food considered by you, things like that etc..
Lets get the unseen details out in the open, & from there we can do a through discussion.

captivereefs, 5 years is great, & about average. Can you speck out your fish, corals, critters & how deep DSB in what size tank. When you change water how do you do it without disturbing the bed. DO you blow off rocks, skimmer how is it set up? You say you feed heavy, so what do you consider heavy? Teaspoon of food every day, or a 1/2 gallon tub? Sorry but If we're going to do this I want to learn what you're doing that works so well, general statements without information to back you up doesn't help.

 

[NaH2O]

Scooterman,

Thanks for saying what I was thinking.....this is what I'm looking for. Oh, and the cool picture of Rogue's sand bed.

 

[Cougra]

I currently have a sandbed that's about 3 inches deep in my tank. I just added the southdown a few weeks ago because I felt my tank was in the process of crashing: uncontrolable algae problems, nitrates levels were climbing and animals started to react differently then normal. I had oringinally set the tank up with a 1 inch layer of large crushed coral and as it slowly desolved I would add more CC.

I think I have a medium size bioload for the size of tank that I have with 4 smallish fish (2 A. ocellaris, 1 royal gramma, 1 lawnmower blenny) and a lot of crabs.

When I do a water change, I do a light vaccuming of the top of the sand without disturbing the sand too much. I feed a pinch of food twice a day: once in the morning and once at night.

Even with the debats going on about sand beds being time bombs and with the risk of having to redo my tank agian in another 4 to 5 years, I still felt that in my system the benifits and nitrogen reducing ability of the sand bed will outway the risks.

I think we learn more about the way these systems work, we'll be better prepared to deal with the problems when the time comes.

When I set this up, I planned change out part of the sandbed each year to export some of the detrious buildup, provide new area for infauna to spread to, and prevent major clumping of the entire bed. I will also be occasionally purchasing new rocks on occassion to help provide some biodiversity in the tank and introduce new genetic streams into the system so that my critters can reproduce healthy offspring. (Would get some detrivour kits if they were more readily available.)

I figured that I'm willing to spend money on upgrading tank size or lighting or getting new fish, inverts or corals, why not spend some money on maintaining good filtration system?

 

[captivereefs]

I never reallly added a cleanup crew. I have a few nassarius snials and one brittle star. M tank isa 45g I always figutred the idea behing a DSB was to let the sand bed fauna clean the sand bed of detritus. I also run a small macro refugium and a remora skimmer. I think most people put to many cleaning organisms in their tank and rob the DSB of the food it needs to fully develop. I nkow i go through critter cycles. For 3 months my pod popultaion will explode. Than it dies back and is replaced by something else. Pretty amazing really. I have 2 damsels 1 clown 1 bi color blenny and 1 yellow tang. I do water changwes when i feel lke it. Sand bed is 5" of aragamax.

 

[sharks]

Ok I’ll go
I have 2-3 inches at the most in my tank and 4 in the REF.
My system is only 14 months old so I am by far no expert here.
I keep few fish in my system. The ones I do keep are workers. Kole, and Yellow tangs, algae blenny, rabbit fish, and a few others. I feed them very lightly…1 cube on mysis, 1 of 100% pro-veggie, and 1 brine every other day at most. I am a firm believer that the less you put in the better. I feed Tahitian blend at most twice a month and only a few drops.
I also believe that the more you physically remove the better. While in a bare bottom tank this is easy, I still clean my overflow sponges nightly. My filter pads weekly. And I change a lot of water. Every Sunday I change about 25 gallons and when I do this I siphon water from the rocks only. I see plenty of detritus come from all the holes and crevices. I pump alot of water in the tank to keep waste in the water column in order to get it into my sponges. It took some time and carefully placed LR to achieve the water flow with out sandstorms.
I keep a cuke, and lots of snails to help maintain the bed.
I have no issue removing a small patch of LS here and there in the future. If done in small amounts using a siphon why not. You have the added security that you are removing the waste. And to me it’s more important to add new life to the tank. I enjoy watching the micro life as much as the corals and fish. So I would gladly add new critters when needed. Maybe in another year I will start removing say 2-3Lb patches and replace that with new LS from local reefers or online vendors. Like anything else if done SLOWLY what will I hurt?
Well that’s what I do and my plans for upkeep on my reef. IMHO a sand bed is just another filter and it needs to be maintained at some point.

I could be totally off base here. And if I am please tell me so. I am learning like everyone else and if you think my plans will create problems I want to know.
See tank description below.
S

 

[NaH2O]

Michelle and sharks...I agree with slowly replacing portions of the sand bed. If you are going to run one, then you need to do maintenance on it like any other filter. Michelle, I liked your statement:

I figured that I'm willing to spend money on upgrading tank size or lighting or getting new fish, inverts or corals, why not spend some money on maintaining good filtration system?

.

Michelle, do you have any ideas on what was causing the tank crash?...maybe the CC?

 

[mojoreef]

I was wondering why the replacement of sand?? I am not sure I follow this.

Mike

 

[NaH2O]

Mike, my understanding (correct me if i'm wrong...which i'm sure i am), of sand replacement, is to keep some of the sand from clumping and holding onto the undesirables, such as phosphates. In my mind, it is similar to pruning macro algae...nutrient export. Get rid of it before it eventually leaches back into the system. Every so often introducing a small amount of fresh live sand with a detrivore kit of some kind...will keep the sand bed from exploding, like Rogue's picture....

 

[Scooterman]

Thanks for the information everyone, so Mike Is picking into what will become a good discussion I hope

 

[mojoreef]

Mike, my understanding (correct me if i'm wrong...which i'm sure i am), of sand replacement, is to keep some of the sand from clumping and holding onto the undesirables, such as phosphates. In my mind, it is similar to pruning macro algae...nutrient export

Ahhh Ok I got it. Hmmm... I wouldnt bother if it were me, The sand is phosphate saturated before it even comes out of the bag. so it wont do much to replace it. The clumping is cause by hard water (which we want) with the lack of stiring, in the case of DSB's by bugs I guess. The phosphates bound in the sand will not leach back into the tank unless a couple of things happen. One is if they are dropped inot a lower zone of the bed in which the ph is low (whih is what is ahppening already in the lower depths of the bed) and or it is melted by bacteria trying to access the food source (which is already going on anyway). So thier is no real method for beating this part of the equation, basically you must live with it. The other way that phosphates enters the bed is through food/waste/detritus, this stuff is what loads into the pore water of the sand bed, this is the only stuff you really have a chance at exporting, but again the only way is to physically remove it, which tends to go against most DSB mantra..


Mike

 

[NaH2O]

OK...so let me see if I have this right....there is no way of preventing the phosphates from getting into the sand bed, because it is already present in the sand, and essentially it will leach....because if it's in the sand then it is going to be in the lower zone. However, I can control the top portion by syphoning the upper layers, say during water changes, and having good water movement trying to keep the detritus in the water column. What about trying to keep the critters in the sand bed fed in order for their job to be done. If I keep removing their food source, then I potentially won't have critters. What changes can I do to the system to make it work? Maco algaes in the fuge to absorb the phosphates, etc.?

 

[Scooterman]

You won't remove it all & whatever you have left over the critters will populate according to what is available. Ok so what you have less critters that the rest, your bed will have a better chance of living longer right?