Maybe I am answering my own question, but I guess water changes will lower my ph level. I am at 8.0 right now, would like to get down to 7.4 area. All othe levels are at the big zero, so I am happy with that. I have a Tiger oscar, JD, two Convicts, two Pictus Catfish, and a Red Devil all except the cats are small, around the same size. Except the red devil is a fry, but does not matter, he chases after the catfish.
