So, this may seem awfully stupid to ask but when your fish has been used to a certain environment for its entire life is it still dangerous to improve your fishes living environment? I have a basic goldfish living in a small 1.5 gallon tank. I have had it for 11 years. Recently he has had two episodes. He was laying on his side...I thought he was a goner....just "getting old" Now he is appearing to have something protruding out of his side?! I'm just wondering if improving his water conditions would help fight off whatever diseases he has gotten or if it would be too much of a shock to him?