I think it was TRL #11 the Co-Sponsor (not sure of his name) said he pumped water through a 5 gallon bucket of sand and this reduced his nitrates. Was this live sand? I thought nitrate reduction occurs in anerobic conditions. Pumping oxegenated water through live sand doesn't seem like it would be anerobic? Am I wrong/missing something? I'm looking to combat a never ending algae battle with a lower maintenance method than sucking it out/changing the water every week. I do run a Phosban reactor and it seems to have helped. Raising my Alkalinity to 8.2 AM/8.4 PM seems to have helped to with hair but now its slimy green, brown and or red--layers on the sand/rocks. I used to drip Kalk but it makes such a mess in the sump (white film that eventually falls to the bottom). Anyway, I might try the bucket thing if it might help and if I can make some room for it under my tank. And I'll look up that Marine S.A.T product you talked about.

THX!!!

I believe Bobby has now removed the standpipe from his RDSB and just has water flowing across it. Your understanding is the same as mine. Anaerobic conditions is what you want in a DSB, remote or not.

I have seen the RDSB work for a guy that has a 300 gal FOWLR with big angels, tangs and triggers and other fish. This is a ripe situation for out of sight Nitrate readings yet, he reported the nitrates ranged from 5 to 10 ppm, a very acceptable range. Of course, he was also doing the normal maintenance things, like water changes, too.

You can start with dry (dead) sand and seed the top with LS if you want or just let it go "live" on it's own. Once you start the water flowing it will inoculate the DSB with the bacteria from the DT. If you wanted to speed the process up without buying LS, put a piece of LR on top. That will seed it, too.

Dick

what about building a system much like what is shown in TR Ep88?

Dick, I heard about your system with the 5g bucket and I was wondering are u still pumping water down a tube into the bottom and trickle up?

John, that's not the system I use. I'm an ardent fan of DSBs in the DT and sump/refugium. But, no you don't pump water to the bottom and allow it to trickle up. You should introduce sand borrowing worms, such as the Medusa worms, Loimia sp, shown on pages 170 & 171 in "Reef Invertebrates"or Sipunculid Peanut worms shown on page 183 in the same book by Calfo and Fenner. Here are pictures of those two worms...

http://www.theculturedreef.com/worm2.JPG




http://www.theculturedreef.com/peanut%20worm1.jpg


The action of the worms crawling through the sand is how the water is drawn into the lower anaerobic layers where the Nitrate conversion occurs.

Dick

Nassarius snails work the top couple of inches, but the worms really dig down deeper.

Dave

oh very nice ty. i was just listening to a tr live ep lately and one of the hosts described using a 5g bucket of sand and pumping water through a pipe to the bottom of the bucket

Thank you FishNerd for asking and thanks to Dick for answering. I am finally moving into a new flat and will be setting up my 120g system and this helps out a lot because I was thinking of going with a SSB(approximately 3 in) in the DT and doing DSBs in the fuge(3 in to 4 in) and in a section of the sump(6 in plus). Do you think this is enough DSB to keep my nitrates down?

Pescaiolo,

That's hard to say with certainty. It will help. The 3" in the DT may get a little anaerobic activity. If you do 4" in the refugium that definitely will and the 6"+ will be the main de-nitrater. I could be enough. You still have to monitor it with test kits as all of us do. Keep up with water changes, use RO/DI and you will probably be OK.

Dick

Thanks to all for your responses. I will check out episode 88 John. Given the information, I adding a dsb to my sump may be an easy solution for me. It isn't huge but I could probably put 4 to 6 inches deep by about 10 or 12 inches square (display is a 125 with a ssb). One comment from the show though was that the DSB should not be lit. I'm growing Chatemorpha (sp?) in the sump now so I keep it lit at night. Given that people keep a dsb in their dt, can it really be that big a deal??? THanks again for all the comments.

Whoever said that a DSB should not be lit is totally wrong. It doesn't have to be lit to be active BUT, DSBs in display tanks are obviously lit for long periods of time.

Dick

Oh by the way, FishNerd, welcome to TR.

Thanks! I've listened to many of the podcasts (while either driving, running or biking) over the last year or so but time is scarce. Fishnerd is a pretty lame name huh? My wife called me that a couple times... Anyway, thanks. Cheers.

Dick those are great pictures!

FishNerd, my family calls me stuff like that too. :)
In the one TRL pumping water down into a 5 gallon bucket full of sand was mentioned. There was discussion on the show about that and through that discussion and additional research he found that he had misunderstood the directions for the RDSB. He was having nitrate reduction with it but I think that was because the pipe was not all the way to the bottom and the anaerobic conditions had developed in the last few inches of sand.

Whoever said that a DSB should not be lit is totally wrong. It doesn't have to be lit to be active BUT, DSBs in display tanks are obviously lit for long periods of time.

Dick

now i can not for the life of me find where it said to cover the bucket to reduce lighting the RDSB !! i WILL keep looking though.

now i can not for the life of me find where it said to cover the bucket to reduce lighting the RDSB !! i WILL keep looking though.

Calfo's prescription for the RDSB bucket has it covered for mainly two reasons. Reduce oxygenation and to prevent undesirable algae growth. Also, unnecessary Algae growth (diatoms/cyano/dinoflagellates, etc) could ostensibly clog the outlet and create a flow problem, and I assume it could also reduce efficacy by preventing (slowing) diffusion of water if the algae is coating the surface (and therefore no need for snails/worms/et cetera to peturb the surface). Calfo claims there is "No benefit and little harm/inconvenience to illuminate the remote DSB" (http://www.reefcentral.com/forums/showthread.php?s=&postid=5901682#post5901682).

Use just enough flow (ie.. 250gph in a 5 gal bucket) to keep detritus from settling. Use a powerfilter foam block to diffuse incoming flow if necessary. Sand should be 10-11" deep. Preferably oolitic so as to reduce trapped detritus.

i know i saw it somewhere in one of the threads, but the threads have gotten SOOOO long (both RC and Marine Depot) that i was getting blurry vision looking through them. lol

i will look again today, hopefully this time, i can find the exact Calfo post.

i know i saw it somewhere in one of the threads, but the threads have gotten SOOOO long (both RC and Marine Depot) that i was getting blurry vision looking through them. lol

i will look again today, hopefully this time, i can find the exact Calfo post.

Did you follow the link in my last post? Calfo pretty much states what you are saying. Are you saying there another post with more detail?

Whoever said that a DSB should not be lit is totally wrong. It doesn't have to be lit to be active BUT, DSBs in display tanks are obviously lit for long periods of time.

If you light your RDSB I'd also recommend seeding it with live sand the same way you would for a display tank DSB or you may notice the top inch or so of the substrate getting "spongy" due to algal buildup that isn't being consumed. I have 1 lit and 1 unlit and haven't had any issues... although I usually refer to the lit one as the "refugium", heh :)

Something to note here is that a DSB in your display tank is (mostly) a biological filter/process, making use of surface critters, their food chain (algae, cyanobacteria, etc) and their stirring activities to transfer nitrate laden water to the low/no oxygen areas where the denitrifying bacteria make their home. In an RDSB, most of the nitrate gets to that bacteria via physical processes, namely the constant and consistant laminar flow across the substrate surface (often more laminar flow than you'd ever want in your display tank unless you keep a lot of gorgonians or something) which results in a fluid dynamic known as advection -- zillions of little vortexes that drag the fluid down through the substrate. I believe this also why an RDSB can be a lot deeper (18-20") than a typical in-tank DSB and still be extremely effective.

One other thing that I didn't hear mentioned that I frequently only hear about after it's too late is to be careful with any dosing that affects pH (kalkwasser, etc). Large fluctuations in pH are how deep aragonite-based sandbeds become solidified or "cemented". I'm not sure if pH fluctuations can also affect quartz/silica-based deep sandbeds but most livestock don't like big fluctuations either so I'd avoid them either way (disconnect the feed to the RDSB if dosing in your sump, etc...)