DSB in a bucket for nitrate control

Here is my 11 month update---

In my case I don't believe I had a big enough sand volume to keep up with my load-- 50 pounds of sand in a 5 gallon bucket on my 135 gallon display lightly stocked tank with a 20 gallon sump...

I added my RDSB on Jan 3, 06--- In May (4 1/2 months later) my nitrates were virtually unchanged (40-50 ppm)....

On May 19th, I added a 29 gallon refugium with a decent ball of chaeto and a 65 watt Lights of America Flourex Floodlight--- after the addition of the Fuge... the nitrates still tested over 40 ppm (on a 160+ gallon volume)... but the chaeto growth took off--- and my nitrates started dropping about 10 ppm per month... I started trimming the chaeto back in August when the Fuge was about full and have been trimming it every week or two since then...

As of this past saturday they tested at 1 ppm by my Salifert test kit...

IMHO... an RDSB has and does work but I would aim on the high side of volume-- about 5 gallons sand per 50 gallons of volume is a good target IMO...

I think I'm going to remove my RDSB though... its outside my stand and kind of in the way and an eyesore-- I think I have a large enough fuge/chaeto volume to keep up with my trates....
 
i should add that my results definitely are not due to the RDSB alone, i also

do 40g water changes monthly ( or (2) 20g )
have 20g refugium with chaeto
and i skim like mad

it's the combination of these that has kept me down at 0.

i'm planning a new pre-sump sump to run my skimmer and a series of 2- 4 RDSB's. each 'cell' would have 50 - 60 lbs of sand and could be replaced at any time. if nitrates start creeping up just put another cell in. then every 2 years replace the cells ( have to keep schedule with dates ). i'm planning ahead for my next tank, probably a 225 but would like to get this running on my current tank.

hey spuds why don't you post and let us know if your nitrates start going up after you take the RDSB out, please :rollface:
 
<a href=showthread.php?s=&postid=8684874#post8684874 target=_blank>Originally posted</a> by a4twenty

hey spuds why don't you post and let us know if your nitrates start going up after you take the RDSB out, please :rollface:

Will do... :)
 
just started a 55 gal drum dsb in the gh. What a job that was getting all that sand down the small hole at the top(closed head drum) Didnt want to cut a lager opening due to the fact that I want zero light inside . will feed water to it by way of a large rk2 skimmer. Had to borrow my sons plastic skate board ramp to sit the drum on(permently borrowed)He doesnt know it yet:D But he just made a valuble contrbution to my opps:)
 
Another update on my system

its been 3 weeks( i think) since I took the bucket off, and my nitrates have leveled off in the 15ish range.

I will now try a new bucket using a bag of live sand(at the bottom) and the rest play sand. Should have that up and going in a week or two.
 
<a href=showthread.php?s=&postid=8713762#post8713762 target=_blank>Originally posted</a> by EnderG60


I will now try a new bucket using a bag of live sand(at the bottom) and the rest play sand. Should have that up and going in a week or two.


If the sand is live, you don't want to bury it. You would be better off adding the live sand on top (or very close to the top).
 
hmmmm, did i miss something? i thought there was no point in using live sand in a RDSB. something about wrong type of bacteria ............ guess i'll have to back track and see if i missed something.
 
<a href=showthread.php?s=&postid=8717716#post8717716 target=_blank>Originally posted</a> by a4twenty
hmmmm, did i miss something? i thought there was no point in using live sand in a RDSB. something about wrong type of bacteria ............ guess i'll have to back track and see if i missed something.

There are two basic types of bacteria at play here. One can live in an oxygen rich environment, one can't. What you get in a scoop of another reefer's sand is Aerobic bacteria, which live in an oxygen rich environment. IF there is actually any live bacteria in that "Bag 'O Live Sand" from the LFS, it's also Aerobic bacteria. If you added that live sand to the bottom of a bucket, with 100 lbs of dead sand on top, you would have a bucket full of dead sand.
Now, Aerobic bacteria will do you no good at all, if your aim is to lower nitrates. Aerobic bacteria consume/convert Ammonia through nitrite, and on to nitrate. You need Anaerobic bacteria to convert nitrate to nitrogen gas.
 
but that is what i'm saying. a scoop of sand from a tank will contain aerobic bacteria ( unless taken from another RDSB ). i agree that putting that sand under 6" of fresh sand will only starve that bacteria of oxygen. i don't see how putting it on top helps either, it's still the wrong type of bacteria.

now that i look back he says a bag of live sand, maybe he's not talking about taking it from another tank. if you buy a bag of live sand from the store there is nothing live on it and IMO it's no worth the money.
 
yeah that was my bad i ment live on top, and I was under the impression the use of some live sand on top would speed up the "curring" process of the anaerobic stuff.
 
Nope, they are two completely different types of bacteria, and they feed on different nutrients.

I'm with you 100% on that bag of sand thing, a4twenty. I've never believed that it was anything other than wet sand.
 
Flow through rectangular RDSB

Flow through rectangular RDSB

I am redesigning my sump/fuge and wanted to incorporate a RDSB. I also wanted to make it larger than the 5gal capacity, so I've been thinking of HOB type RDSB or other rectangular channel.

It seems to me that the flow straight over the top of the 5gal round bucket is not optimal with the center getting more flow than the edges. So I was thinking basically of making a long/narrow channel tank for the RDSB. Proportions roughly 45"length x 6"width and 18-24" in height. This would allow for a deeper RDSB and a more uniform linear flow over it's entire surface. Does anyone have any thoughts on this? Would it be beneficial?


On a similar concept, another stray thought going through my head is that I could convert my 55g sump into an RDSB, but in this case I was thinking of using some dividers to create a set of narrow channels to have a serpentine flow.

In the case of using a rectangular 55g for such purpose I'm curious if anyone has thoughts between two approaches that could be taken.
a) A slow/wide flow going one tank length from one side to the other
vs
b) A faster/narrower flow traversing the length of the tank several times. Still linear, but narrower and about 2-3 times the length.

117393RDSB_flow.jpg


I'm wondering if there would be any advantage to a longer travel time.
 
<a href=showthread.php?s=&postid=8718334#post8718334 target=_blank>Originally posted</a> by DgenR8
There are two basic types of bacteria at play here. One can live in an oxygen rich environment, one can't. What you get in a scoop of another reefer's sand is Aerobic bacteria, which live in an oxygen rich environment. IF there is actually any live bacteria in that "Bag 'O Live Sand" from the LFS, it's also Aerobic bacteria. If you added that live sand to the bottom of a bucket, with 100 lbs of dead sand on top, you would have a bucket full of dead sand.
Now, Aerobic bacteria will do you no good at all, if your aim is to lower nitrates. Aerobic bacteria consume/convert Ammonia through nitrite, and on to nitrate. You need Anaerobic bacteria to convert nitrate to nitrogen gas.

To elaborate on this I would like to add that there are 4 basic kinds of bacteria.....non- obligate anaerobic, obligate anaerobic, non-obligate aerobic and obligate aerobic. Aerobic bacteria will die under 6 inches of sand only if it is an obligate aerobe. The same is true for anaerobic bacteria. If it is not an obligate anaerobe, it could survive in an oxygen rich environment.
So when adding live sand to any system. The bacteria that ends up growing in the bottom layers could be the very same bacteria that is thriving in the upper layers just producing energy with different pathways. Ofcourse its not as black and white like that , in the end there wil be a mixture of obligate and non- obligate aerobes and anaerobes thriving in deep and shallow niches.
 
Re: Flow through rectangular RDSB

Re: Flow through rectangular RDSB

<a href=showthread.php?s=&postid=8752835#post8752835 target=_blank>Originally posted</a> by ScooterNH
I'm wondering if there would be any advantage to a longer travel time.

i would have to say yes, the longer the dwell time the more denitrification can take place. the reason we use more flow is to prevent any fall out from the water.
 
woundn't the feedng tube stuck to the bottom will reintroduce oxygen to lower levels renderring it innefective?
 
i'm not sure why you would want to 'feed' carbon? i may have missed something here? but i'm with tekcat how do you stop the air?
 
Back
Top