Anaerobic filter help

RyanFish · Jan 11, 2020

Hi all,

Any suggestions on a good anaerobic filter for a fish only tank. I have a 6 foot closed filter tower full of porous pumice stone. Water pours in slowly from the top and falls to the bottom then dumps into the sump. I charged the pumice with bacteria and a bit of vodka.
My pumice is now stained with methylene blue and probably some rid ich. I do not think it works anymore. Not even clorox removes the methylene blue. Also the pumice no longer floats, which I think means all the pores are clogged. Should I buy new pumice? Should I leave it alone? Any other filter media I should put in instead? Is my approach to an anaerobic filter completely wrong?
Any suggestions would be helpful.

Shawn.B · Jan 11, 2020

when i think of an anaerobic filter i think of those filters that had 200' of 1/4" line and a flow rate of a few drops a second, im not quite sure what you have is an anaerobic filter more of a trickle filter?

Scrubber_steve · Jan 11, 2020

RyanFish said:
Hi all,

Any suggestions on a good anaerobic filter for a fish only tank. I have a 6 foot closed filter tower full of porous pumice stone. Water pours in slowly from the top and falls to the bottom then dumps into the sump. I charged the pumice with bacteria and a bit of vodka.
My pumice is now stained with methylene blue and probably some rid ich. I do not think it works anymore. Not even clorox removes the methylene blue. Also the pumice no longer floats, which I think means all the pores are clogged. Should I buy new pumice? Should I leave it alone? Any other filter media I should put in instead? Is my approach to an anaerobic filter completely wrong?
Any suggestions would be helpful.

Sounds like you're describing an old trickle,,, wet/dry filter ?
For any media to become anaerobic it needs to be completely submerged.

DangerDave · Jan 11, 2020

Shawn.B said:
when i think of an anaerobic filter i think of those filters that had 200' of 1/4" line and a flow rate of a few drops a second, im not quite sure what you have is an anaerobic filter more of a trickle filter?

With that very slow flow you get anaerobic bacteria and nitrate reduction. Same effect as if you have a very low flow area of your sump with a bunch of rock or marine pure.

DangerDave · Jan 11, 2020

RyanFish said:
Hi all,

Any suggestions on a good anaerobic filter for a fish only tank. I have a 6 foot closed filter tower full of porous pumice stone. Water pours in slowly from the top and falls to the bottom then dumps into the sump. I charged the pumice with bacteria and a bit of vodka.
My pumice is now stained with methylene blue and probably some rid ich. I do not think it works anymore. Not even clorox removes the methylene blue. Also the pumice no longer floats, which I think means all the pores are clogged. Should I buy new pumice? Should I leave it alone? Any other filter media I should put in instead? Is my approach to an anaerobic filter completely wrong?
Any suggestions would be helpful.

I’ve never used this type of filter, but i understand the idea. If you think the media isn’t effective anymore can’t you just change it and start over?