Did I see another Hippo Tang with Ich on this page? We should change the name to "Icho Tang". I tried so many things last year when I went thru this that I can make some observations that that are very solid.
As to Ich's resistance to hyposalinity, I stated about a month or six ago that I felt that I had a strain that got used to low salinity and could not be killed by it. We joked a little calling it the guyguerra irritant strain, but I believe as this thread goes on there will be enough cases to prove that hypo is not a guaranteed treatment for Ich, and I believe it will continue to be less effective as strains build immunity to it.
As to Cupramine, I had several conversations with the guy's at Seachem, both by phone and emails. They are a great group of people and an excellent company. Anyone thats used the color scale will agree that it's hard to read, but they also send a sample bottle to help you get started. The effective range for dosage is broad. Anything between .2 and .8 is therapeutic. They recommend .5. If you use the sample water sparingly, you should have enough to do side by side comparisons for about 5 tests. If you run out of sample water, buy another kit. The price compared to the effect is cheap.
As to test kits, I started my first Cupramine treatment with an Aquarium Pharmaceuticals test kit because thats what the LFS sold me when they sold me the cupramine. I had the levels set at .5 but didn't see any effect. Then I got a Red Sea kit and said WHOA, this chart doesn't even go high enough. So I drove 40 miles to the next LFS and got a Seachem kit. I compared all three, every day, until my wife was convinced to baker act me. What I concluded is that you should only use Seachem test kit with Cupramine, nothing else.
As to toxicity. I'm not a biologist, but I have a copperband that went thru treatment, and is now a year and a half "into recovery" and looks forward to eating out of my hand every day. My Foxface, Threadfin butterfly and two clowns also think highly of cupramine. I try not to think of the losses I had during the duration of failed hypo treatments and incorrect copper levels due to using the wrong test kits. I lost about 8 fish during that time. Now I go directly to using Cupramine in my QT if I see Ich, and they aren't stressed by me botching things up or taking too long in treatment.
As to Cupramine's effect on a tank. I've heard so many people tell me that once you use copper in a tank you an never use it for a reef. This is a myth. I treated my first fish in my 120 gallon display because my LFS didn't tell me I should start with a QT. I later sold the tank to my brother because he was going to do a FOWLR. He ended up building a beautiful reef in it. It looks great, and all his corals, anemones, inverts and fish are doing great.
I've also seen the articles saying to keep a spare tank empty, and keep a sponge in your display for bio, then magically put it together when you need a QT, a wala, you can throw your fish in it. Thats nonsense. I keep a 50 gallon tank year round so that when I need it, I can count on it. When I buy a fish, thats where he lives until he gets his health approval from me. The first spot of Ich, I dose with Cupramine. In about 4 weeks he's probably going to be ready to go into the big tank. If he dies, he was probably going to anyway.
There are a lot of myths about treating Ich, but it doesn't need to be that hard. What I outlined above is fairly simple. You can get by with a nano tank for a QT if you like. Put your garlic on your pizza and drink your hypo water, put copper in to treat Ich, and everyone wins.
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