Ever since I set up my tank 2 years ago I have been battling a perpetual white spot problem with my fish. I am reluctant to call it ich b/c it may not be c. irritans(I have gone as far as to remove the fish for 1 month). Every morning I wake up, my fish have white spots on their fins primairily. Then 3 hours later the spots are gone. I run a 9w UV sterlizer in my sump. Water parameters are perfect. I don't understand why I cannot fix this problem. Should my UV be in the main system rather than the sump? Even if I take the fish out and medicate them it will return when I place them back into the tank. Plus taking them out would mean disturbing my entire system. Any advice would be greatly appreciated.