OKay, I built a setup to return all the water from my wet/dry filter under the gravel. I was thinking it would keep the waste from sinking into the gravel substrate. It might have with fine gravel, but I wanted something larger in my 90G, so I used a layer of small and then a layer of river rock looking gravel.
I did regular water changes and gravel vac'd like my smaller tanks.
A couple aof weeks ago, my nitrite started going up for an unknown reason.
I kept it under control with water changes, but could not stop it.
I think I finally figured it out. The combination of current in the gravel and larger rock on top was allowing waste to sink much deeper into the sibstrate than I am used to.
I did a major gravel vac, shoving the vac deep into the substrate and was pulling up tons of waste.
So I guess the waste was decaying at a rate the ammonia to nitriite bacteria could keep up with, but the nitrite to nitrate could not.
I suspect with the massive bio-area of my wet/dry it might have been able to eventually cope, but still not ideal.
I will do another deep gravel vac this weekend and remove the under grvel return.
I did regular water changes and gravel vac'd like my smaller tanks.
A couple aof weeks ago, my nitrite started going up for an unknown reason.
I kept it under control with water changes, but could not stop it.
I think I finally figured it out. The combination of current in the gravel and larger rock on top was allowing waste to sink much deeper into the sibstrate than I am used to.
I did a major gravel vac, shoving the vac deep into the substrate and was pulling up tons of waste.
So I guess the waste was decaying at a rate the ammonia to nitriite bacteria could keep up with, but the nitrite to nitrate could not.
I suspect with the massive bio-area of my wet/dry it might have been able to eventually cope, but still not ideal.
I will do another deep gravel vac this weekend and remove the under grvel return.
