I’m not new to aquariums but I’m having issues I can’t seem to solve.
I bought a used 60gal tank two months ago with a few large fish. Immediately I discovered the tank was too small for the fish I had, so I rehomed two fish and bought a brand new 90gal tank about 3 weeks ago. In the transfer I seem to have disrupted the cycle. I have consistently 0.25ppm Ammo, 0 Nitrite and fluctuating Nitrate, 10-40 depending on how close to last WC
. I have been treating with Prime, Stability (to speed up new cycle) for just over a week. No change. Any ideas on my ammo problem?
In the tank: a 12” tiger Oscar, a 10” Jack Dempsey, an 8” common pleco.
The Oscar is really my problem fish. She is stressed. Obviously. She hides and lays on her side all day every day. Oddly, at sundown and when it starts getting dark she suddenly seems happy as a clam. Swimming and playing etc. But only after dark. We have a programmable LED
and it’s only on a few hrs a day, at 40%. But still she hides. No signs of fish aggression. The JD and the Oscar always hang out together. Oscar seems to be the leader. If she hides, Jack hides. If she’s out, he’s out. They both eat sparingly. Oscar eats various foods, even right from our hands, if we approach her when she’s out and it’s dim/dark. Jack D seems to pick stuff off the bottom; we rarely see him eat and he never never eats from the water surface.
I have a well. Water is quite hard. KH8, GH12. PH8. We also have a water softener but do not use softened water here due to its added salts. I have tried several methods (peat, driftwood, chemicals) to get the PH down a little but it has never budged. (Prob too high KH
). As an experiment, I did a PWC
and added 15gal of distilled water. This dropped the hardness to much better levels and the PH to 7.8. I was happier and the fish had a really good day- they were very active that day and I thought I had it fixed. Next day, PH was back at 8. Why?!? The substrate is commercially available aquarium river rock. Various types of stone in there. Would pictures help?
Then, I bought a Reverse Osmosis unit. I have not yet used this water but I plan to use some in a WC
tomorrow. Similar to the distilled water I got, it has low hardness and PH is mid-7s.
Filtration: I have two large HOB
filters (no carbon) with 2 layers of sponges of different densities. (Emperor 400 and Emperor 350). One filter also has Zeolyte to hopefully help with ammo. And I have two large sponge filters running. Am I perhaps over-aerating?
So the bottom line:
-why is this Oscar so terribly stressed after two months?
-what happened to my cycle, and what should I do about ammonia?
-how can I keep my PH in check, hopefully stable at 7.6-7.8?