I have a 29 gal high with an AquaClear 50 HOB filter and an sponge filter that *was* established and doing awesome… until it wasn’t. It houses 13 cories (6 pandas, 5 albino, 2 emerald), a mystery snail, and a female betta.
I can’t pinpoint what caused the crash, but at some point my nitrogen cycle crashed with fish in the tank. I’ve lost 4 fish in two weeks because of high nitrITES. (I capitalized that on purpose)
Filter media is:
course sponge,
crushed coral
Aquarium Co op bio rings/Fluval bio beads
and I had SeaChem Purigen in there, but I decided to switch it out for a piece of fine poly pad today since nothing else is working.
When this saga started, ph was very low, but thanks to some crushed coral, that’s come up.
Water parameters are:
Ammonia 0
pH 7.4
nitrate 5
nitrite currently at 1.0, but if today is like all of the past 14, it will be back up near 4.0 by bedtime and I’ll spend the night berating myself for not doing a water change at midnight and hoping my fish are alive when I wake up.
I’m going through SeaChem Stability at a ridiculous rate with no results.
Every day, I do my water check, do a 30% water change to bring the nitrites back down, dose with Fitz water conditioner and Stability, check parameters again (water change usually gets me to a nitrite level of 1.0) and by night it’s back up to danger level.
What am I doing wrong?
This tank was cycled fishless for almost 4 weeks, until parameters were spot on and stable for over a week. I added fish, everything was great for a month or two and then it stopped breaking down Nitrites. My water is RO water, it is a little soft, but has no nitrite reading alone.