I don’t have a skimmer or any other form of filter (except 3 sponge filters) in this 50G hospital tank. Thanks and I’ll let you know how this works for me in 4 weeks. Jim PS – I lost the power blue tang to this “super ich” strain a few days ago. The rest of them seem fine though. I started the “no light” part of this treatment a couple days ago, just to see how they would behave / react to feedings, etc. They seem very skittish with no light, but did eat all the food I put in (from bottom of tank as opposed to how they normally come right to feeding site at top of tank). Not sure how this lack of light will affect them for 1 month? Sounds like many other hobbyists have done this previously, so I guess they will be fine.