Removing a GARF style DSB need advice

vance.110 · #1 01/04/2008, 09:02 PM

I'm thinking of removing my deep sand bed and want a little advice. I know I shouldn't do the whole thing at once without removing all of the inhabitants. Can it be done a small amount at a time over a longer period of time and keep everyone in the tank? I was thinking of using 1.5 " hose and just siphoning off water and sand at the same time, and maybeing doing 5 gallon water changes 2 times a week until it is all gone. The biggest problem is I set up the DSB the way GARF describes it with about an inch of space under the DSB that has nothing in it used as an anaerobic space to lower nitrates. Sooner or later I'll have to disturb this area. Any ideas on whats going to happen?
Any help would be appreciated.

Thanks,
Bill

Lincutis · #2 01/04/2008, 10:28 PM

Yes, you can do small amount at a time, and you should. If you take it all abruptly you will lose a major filtering system.
Syphon small amounts at a time over as long a period as you can to allow the biofiltration to adjust.

mrwilson · #3 01/04/2008, 11:55 PM

I'm actually thinking of doing this also. Bill, what convinced you to get rid of your DSB?

vance.110 · #4 01/05/2008, 12:09 AM

I'm thinking of going to a bacterial based sstem like Polyp Labs or zeovit... I know I know the dreaded z word. My biggest concern is nutrient export, I just do not think I can possibly keep up with making sure I clean the sand bed effectivly without it turning bad on me. About 8 years ago I had a bed go bad, and gas began to bubble out of the bed, it stripped the water column of all of the oxygen, and I almost lost everything. Back then I didn't ever touch the bed when cleaning the tank, I just siphoned off water when doing a change. I now obviously try to clean the bed when doing a water change but man it looks like crap when I'm doing it, I can't imagin that is good for the tank. I feel like I could gravel vac the bed all day and still pull out all kinds of crap. LPS, Ricordia, and Zoos grow like crazy in my tank. SPS even grows well but it just turns brown over a few months, and I'm tired of it. I feel like going with a bacterial based system may mean more daily maintinance, but on a much smaller scale and a lot less of a hassle then the gravel vac every other week. I don't think I'm going bare bottom, just a single shallow layer, probably only about a half inch just for looks.

Sorry about the long post, just venting I guess.

itZme · #5 01/05/2008, 12:29 AM

I have siphoned out sand before and I think you will have a better time of it using hose around 5/8-3/4 instead of 1.5" like you said you were going to use. This way there is less water flowing out and you can take a few minutes to fill a 5g bucket instead of having a huge stream of sand/water and having to move so quickly. I think you have more sand to water ratio with a smaller tube but if you go too small it will clog with larger chunks of rock if you suck up any.

Also watch out if you have any blennies or wrasses that will hide in the sand when scared. I have seen them sucked into a siphoning tube halfway and the results were not good

HTH

cl2ysta1 · #6 01/05/2008, 12:33 AM

we've been doing about an inch of sand on all of our tanks but the 180 and they do great. the sand bed stays clean, and i dont have to worry about it going bad

seandanekind · #7 01/05/2008, 03:48 PM

Siphoning & sandbed question

Does GARF use the coarse gravel and crushed coral & shells, or fine sand, or both? I can't remember...

cl2ysta1 · #8 01/05/2008, 04:04 PM

i think the garf style is a plenum with space between the bottom of the tank and the layers. they do screens inbetween. and water naturally flows through the sandbed. if he has a true plenum he should be able to remove it all at once? there shouldnt be any dead areas

vance.110 · #9 01/05/2008, 05:36 PM

It is set up in such a way that there is 3/4 " PVC along the bottom of the tank covered in nylon screen, then there is about 1.5 " of coarse gravel, then more screen, and finally a few more inches of mixed ruble, gravel and sand. From under the tank you can see the space on the bottom is clear except for a little sand that has made it through. You think I can remove this all at once??? I was worried that I would be taking out too much of my biological filter too quickly.

coralreefer2110 · #10 01/05/2008, 05:52 PM

I am not sure if it will help, I am admittedly new. However I did remove my DSB in a 90 last year and did it using an eheim cannister stripped of any material. It had the smaller diameter tubing and a greater suction than just a siphon. Once the desired water amount was reached. Just kill the power. By the way, I did about 30 gal at a time over a two week period. Just a thought. Good luck!!

cl2ysta1 · #11 01/05/2008, 06:47 PM

well you more than likely have live rock and such in there right? your going to have to move all of that evenutally to get the pvc structure out. your going to keep some of this sand though for filtration right? can you just remove half of it. leave the other half in, and than move the pvc structure out and not really removing the last of the sand your keeping

vance.110 · #12 01/05/2008, 07:34 PM

yeah, sooner or later the PVC has to come out ... I guess it doesn't have to but it would look pretty bad I think. So yeah the rockwork is going to have to be taken out for a little while at least while I pull the pvc up. I've been wanting to re-aquascape anyways so that isn't a big deal. My concern with leaving in some of the old sand is the nutrient build up in it. I know it would be a lot less but I'd like to go to a fine sand anyway. If I do this a little bit at a time stretched out over a month or so the live rock should be able to handle everything right? I've probably got 100 or 125 lbs in there. The bio load isn't very large as all I have are a couple clowns, a chromis, coral beauty and a tang, and maybe 15 or so corals or colonies.