I didn't mean to start a disagreement. I prefer to stay away from any type of chemicals that may hurt my little pond. I was told the melafix would help my little koi and can be used in my pond and not hurt my other little koi that isn't sick and was more of a natural treatment. I'm fairly new to ponding and this is the first sick fish I've had. I was trying to go as natural and as safe of a rout as possible. I'm limited on what is accessible in my area and funds. I wanted others input on the directions of the use of the melafix. The directions on the bottle says nothing about water changes. So I was trying to determine by others experiences if that was suppose to be done or not. Also if there was any hope as to rather it actually worked or not. Thank you for everyone's help.