Hi. I am having a problem in my saltwater fish tank. Some of the fish seem to be developing some kind of parasite which causes them to often itch or have cloudy eyes. Whenever I dip them into fresh water, there seems to be small white oval shapes that have fallen off of the fish (I believe they are called dead flukes). However, the fish in my tank seem to still have the problem no matter how many times i do these freshwater dips. I have no coral or anemones. How can I get rid of this problem. Thank you in advance.