I have three fish in my freshwater tank. All goldfish. They have not been very well. The have suffered tail rot and we have treated this and purchased ph and ammonia test that sit in the tank. The levels of each seem okay on the test strips. One fish is showing signs of improving and swimming around but his skin and scales look bruised. The other two fish are just hiding and don’t seem to be doing very well. They don’t swim about or do anything else. We have been advised by pets at home to minimise things in the tank but not to make it completely bare. I’m lost of what else to do. We have treated for white spot and parasite as to begin with they had white spots, yesterday we treated them with a product called healthy fish produced by love fish company which is sold at pets at home. The ammonia level was a little high when we did a water change yesterday and we have added ammonia removed from the same company to reduce these levels. We have also added aquarium salts. What else can I do?