I know a lot of people have a deep sand bed for natural nitrate reduction. But if you have enough Live Rock, wouldn't that do the same job? So wouldn't it make sense then to have a sand bed and inch or less and that way if you needed to, you could vacuum the sand to get rid of waste buildup. From what I've read and heard, vacuuming a deep sand bed does more harm than good. Also, having a sand bed that you can vacuum, you wouldn't have to rely on a cleanup crew as much right? (except maybe the algae eaters)
Deep sand bed, or an inch or less?
- Thread starter phuntoon
- Start date
JeffersonReef
New member
The more live rock you have, the less sand you need. Also, the finer your sand, the less sand you need for nitrate reduction. If you use oolitic / sugar-sized sand, you can acheive nitrate reduction in like 2 or 4 inches. But as long as you have plenty of LR (1.5 times the total number of gallons), you should be ok. But beware coarse sand beds like crushed coral. They are a detritous trap and a nitrate factory! Anaerobic bacteria need somewhere devoid of oxygen to thrive.
TekCat
New member
In order to process nitrates to N2 there has to be an anoxic zone somewhere, where bacteria will "eat" nitrates.
I far from being an expert but I figured that deep inside LR that zone could form, however my guess that it is going to be quite inefficient in removing nitrates for two reasons. First, IMO, the anoxic area inside LR is not going to be that big (compared to DSB's lower layers). Second, nitrogen gas (N2) is the result of denitrification can't easily escape from the inside of LR, so it will fill up the anoxic space pretty fast, thus reducing size of the zone and making it even less effective.
This is what I've figured, so please correct me if I am mistaken.
IMO, the compromise (in case you don't like the look of DSB, or for other reasons) might be shallow sand bed in tank and RDSB (Remote DSB, or DSB-in-a-bucket).
I far from being an expert but I figured that deep inside LR that zone could form, however my guess that it is going to be quite inefficient in removing nitrates for two reasons. First, IMO, the anoxic area inside LR is not going to be that big (compared to DSB's lower layers). Second, nitrogen gas (N2) is the result of denitrification can't easily escape from the inside of LR, so it will fill up the anoxic space pretty fast, thus reducing size of the zone and making it even less effective.
This is what I've figured, so please correct me if I am mistaken.
IMO, the compromise (in case you don't like the look of DSB, or for other reasons) might be shallow sand bed in tank and RDSB (Remote DSB, or DSB-in-a-bucket).
I'm not sure there's any numbers on denitrification rates in live rock or live sand, but live rock does seem to do a fair amount of denitrification. I don't vacuum my sand at all, so that's not an issue for me. The cleanup crew does that job for me. I don't particularly want to take over the job.
The primary reason I need a sand bed I can occasionally vacuum is, it will be eventually housing an octopus. The tank will be a reef tank with lots of live rock and some non stinging corals and such. The reason I ask about the vacuuming is that the octo will eat any cleanup crew or scavengers I put in there. So I need a medium that I can vacuum and not offset the balance of the tank. From all the searching of articles and posts it seems that a shallow sand bed would be my answer. Is my assumption right??
JeffersonReef
New member
An octopus? In a reef tank? There are some major problems (IMHO) with that:
1 - They are ESCAPE ARTISTS. You will be suprised to see how easily an octopus can escape from an open tank. Thulsy, you will need to keep lid closed, which will impede the nitrogen cycle and also less heat will dissapate
2 - Your octopus will eat any and every living invert or fish that it can stick in its mouth. They are voracious
3 - The octopus is very effective at pulling apart rock structure in your tank. You will come home to find one of your prized corals has been trapped in a avelanche of fiji branch.
Again, just my humble opinion. If you want an octopus... just keep the octopus. Definetly NOT REEF SAFE!
-Tony
1 - They are ESCAPE ARTISTS. You will be suprised to see how easily an octopus can escape from an open tank. Thulsy, you will need to keep lid closed, which will impede the nitrogen cycle and also less heat will dissapate
2 - Your octopus will eat any and every living invert or fish that it can stick in its mouth. They are voracious
3 - The octopus is very effective at pulling apart rock structure in your tank. You will come home to find one of your prized corals has been trapped in a avelanche of fiji branch.
Again, just my humble opinion. If you want an octopus... just keep the octopus. Definetly NOT REEF SAFE!
-Tony
Similar threads
