I recently moved and noticed my fish not interacting. I finally got time to do a water change and test the water. My tap is coming out at 6.0. Maybe lower. I am trying to get some ph UP in the next day or two. Is there maybe something else to test for? Ammonia, chlorine, nitrite, and nitrate are all testing good. I'm using tap water conditioner I always have to remove chlorine and don't see to have a chlorine problem. My test strips are show none in the water. I added feeder fish today after a water change 6 hours earlier and about 6 died. The mollies are fine. I lost the algae eaters in another tank. The angels, gouramis, and tetras are fine in there. Please let me know if there is something else to watch for. From what I've read, high ammonia and nitrite should be bigger factors but those are in check and the ph seems to be the problem.