Many thanks, David and Mark. That is EXACTLY the type of information that I needed. OK. Now I'm thinking QT tank for fish as per standard practice. I'll have to trap that Goby some how. Thing is, access to the overflow is limited and space within the overflow is smallish with 3 dursos and 2 returns - and the pesky little guy is at the bottom. Netting him is impossible. I almost fell in my tank and crashed 4 Vega modules trying to do it once. We will see how I go. I've gotten bits of advice to just let things run their course and see if the fish kick the ich on their own and get some sort of immunity. Thing is I want my fish to thrive and not just survive and if they are feeling bitten or stung or any kind of pain related to ich (even if they have some immunity), I won't be at peace with that. Does a fish with immunity, still feel the pains (pricks, bites, stifled oxygenation from gills being full of it) of ich infestation? The questions just build and build around this. Does any one know of a reputable journal or article or magazine to reference. I am definitely marking my calendar for the Feb 9 BARs event.