i went through this for months as my kole tang, blue tang, flame angel, and several others had ich pretty bad...... i kept doing water changes every week of about 30 gallons to my 125 gallon tank and it seemed to slow it down but it was still pretty bad. I decided it wouldnt hurt to try a UV sterilizer and some skunk shrimp so i did, i put in 3 skunk shrimp and a 36w turbo twist sterilizer and the problem quickly vanished, its been two months now with no sign of any ich and im back to once a month water changes and my tank looks amazing.
