Ick/ich :(

[NeXiLe]

At first only the blue tang and our puffer fish in the other tank had ich, now it seems nearly half the fish have ick. The blue tang(just laying down like thy do under a rock and not eating which is very unusual for him ,) the sailfin tang, the puffer(just sits on the bottom, won't come up to eat and if he does come up, he pays no attention to the food,) 2 clownfish (1 is just swimming with his mouth practically out of the water and not eating anything.) It seemed to spread and get this bad within a few days, all it was before was maybe 2 little dots on the tang and the puffer had cloudyish eyes, it's hard to tell as his eyes are pretty

Anyways, now I'm pretty sure half of them are going to die what should I do? All the tanks are connected, the puffer and a big domino damsel are in 1 tank, a clownfish that got bullied by the other clownfish and another damsel are in another tank and the rest of the fish are in the biggest tank along with some corals (xenia, acrapora [spelling,] and a cabbage coral and a whole bunch of snails and crabs

The only fish that seem to be fine are the gregory damsel, blue? damsel, mandarin goby, the baby clownfish in the big tank and the little green damsel in the lower tank. I know we probably have too many fish and we won't make that mistake again. In the mean time, what can I do to help these poor fish?

[betamed]

Sounds like a bad situation. how big are the tanks? Can one be isolated and used a s a treatment tank? The best thing to do would be to remove all the fish and put them in a large Quarentine tank and treat with hypo or copper for 6 weeks and leave the other tanks without fish for that time. There are other things that can be done, but are less reliable.
Add garlic to food
add a UV
reef safe products such as Kick Ich
cleaner fish/shrimp

[NeXiLe]

55 gallon is the main (reef) tank (I know this is small for tangs but it's a lot better compared to the 20g they were in in the store.) then a 40 (or 45) with the puffer and damsel and the sump which we had a few mean damsels and a bigger clownfish that got bullied in. I'm pretty sure that clownfish is dead, he's swimming around upside down and sideways and looks pretty gross, he was fine 2 days ago. I'm pretty sure he'll be dead soon

I'm not sure how we'd go about isolating one tank, my brother set it all up and goes to work 3 weeks at a time. The main tank overflows into the 40g and that overflows into the sump and is pumped back into the main tank.

Makes me sad all the fish were acting completely fine 2 days ago and now suddenly half of them have it. The puffer ate some krill just a while ago so maybe he's feeling a bit better.

[betamed]

Ya those 2 tangs just won't live long term in a 55 anyway. See if someone who can care for them can take them off your hands. Or maybe you can give them back to the LFS. One of the problems with ick is that every cyst on the fish can hatch into hundreds of new cysts and things get out of control pretty quick. Healthy fish in excellent tank conditions can fight it off, but the tangs are likely saturating the tank with ick cysts and the other fish become overwhelmed as well. If QT treatment is not possible removing the tangs and treating the system with alternative methods might work.