Pompous_Oscar

@Colu I usually do about 40% or so each week. No new fish in over a year. About a month ago, I did remove the Green severum that was bullying all other fish (except the Oscar). I haven't seen any surface dwelling. There was some rapid breathing from the silver dollars during the cycle crash, but not since. No stringy white poop either. @quikv6 I have added some metroplex/focus/garlic guard to some frozen beef heart. She ate a few pieces of it within the last week or so. I would like to increase the KH without too much GH change. Would just like to avoid dramatic PH swings as much as possible. What size is the tank that you added the 1/2 pound to?

No, those pics were from a couple weeks ago. The cycle rebounded. I also changed out from a bubble wall to two large air stones. None of the fish have been having much in the way of an appetite since this all occurred.

I had a Green Severum that was quite the tank bully which seemed to stress the Oscar. Once she developed HLLE, I removed the Severum. About a month ago I medicated the tank with Fritz Prazacleanse. This caused a bit of a cycle crash. Here are some pics of what the Oscar was doing off and on for about two weeks. o weeks.

Thanks for your response. It is a 125 gallon if that makes much of a difference. About how much crushed coral do you think would do the trick?

I recently discovered the importance of KH for buffering purposes. I could not figure out why my 7.0-ish water from the tap was becoming closer to 6.0 in the aquarium. Once I received the test strips from this site in the mail, I discovered the KH in my tank is 0. (ph around 6, 0 nitrite, 10-20 nitrate) It comes out of the faucet at around 25 KH. However, I feel the ph swings are stressing my community tank out. Especially my Oscar. Some suggest alkaline/acid buffer, some suggest things like crushed coral. Any ideas? I'd prefer not to have too high of a PH since it is a community tank. Something natural and low maintenance would be terrific. The 125 gallon tank consists of 1 oscar, 5 silver dollars, and 1 featherfin catfish. 2 FX6 and 1 Tidal 110. The sand is Stoney River and is supposed to be PH neutral. I also have a pothos plant in hydration leca.