thats how the parasite works , being visible is only one stage of what the parasite does.

fwiw if its just a few spots then im with the group and keep him healthy and eating for now unless it becomes severe.

there does come a time though when a fish is gone to far , regardless of the foods or the amounts they wont come back (food is not a cure, the hobby as whole kiows this for a fact) , this i can guarantee . you'll know when this happens and fish usually don't last but a few days at most in this condition.

I've been keeping SW fish for about 10 years and every now and then a new fish will get a few spots and then next day they are gone and don't come back. So you're not alone. I've never lost a fish to ich, not having a top is another story.

I picked up some seachem metroplex and focus. Soaked their food in it and everyone ate it. Hope it helps. I start my last two months of school Monday and just don't have the time to tear down my tank. Guess I'll use the medication for now and once I'm out of school if there are any remaining concerns I'll deal with it then. I spoke with a couple people on the forums here that have had excellent success with metroplex and focus so I hope they work for me too.

Well starting yesterday the ich started to move through the rest of the fish in the tank... I picked up some plexiglass and managed to get all the fish out with only taking out a 1/4 of my rock and everything went back together pretty good. I set up a 30 gal rubbermaid with the filter and some of the water from my other qt tank that has been running a couple months. I'm going to start with metroplex and melafix in the water tonight. Can anyone recommend a good medication to use in my qt. I would like to use something that will kill ich but also covers me for anything else I should be treating for as a preventitive measure. I'm going to keep fish out of my tank for the next 12-16 weeks to make sure the ich is good and dead.

What's likely is that the parasite was already in your system but at sub-clinical levels, kept at bay by the immune systems of fish that have adapted to it. Then you introduce a fish with an innate susceptibility and after a couple of life cycles (a month sounds about right) your tang has shed enough tomonts in to the system that when they start hatching the concentration of infective parasites rose high enough to start overwhelming your otherwise resistant fish. It's like locking a bunch of vaccinated children in a classroom every day with a few who aren't, then exposing them all to measles. Eventually even the vaccinated kids are at risk just from the constant exposure.

If you have the set up, I highly recommend the tank transfer method. Super easy on the fish so long as you control for ammonia, guaranteed effective to eliminate ich from your fish 100% in 12 days, and there's no risk of poisoning them by accident. After that you'll have another 8 weeks to observe them and treat them for whatever else you think is necessary.

SeaChem cupramine works great.

I agree and trust SeaChem Cupramine. It has worked every time I have used it. I now also dose a cycle of PraziPro for all my QT's fish for a few other diseases that seem to be more common with new fish. I start the cupramine on day one, then on day 2 I add Prazi in the day and the second dose of Cupramine at night.

Ok sounds good. I'll go with Cupramine and maybe switch to the prazipro in four weeks when I'm done with the Cupramine. It does say specifically on the Cupramine not to combine it with any other medications and I don't want to add any more stress to the fish then they're already going through.

Smart man , don't add prazi to cuprime in particular, it would not be good:)

Add copper slowly over 3-4 days period. Watch for reaction of fish from copper. Some fish don't tolerate copper that well. Signs of bad reaction are not eating, heavy breathing etc.
Copper is not fun to play with since it's a poison.
Good luck!