Hey everyone. Getting back in the hobby after many years. Have been slowly setting up main DT (100g) and trying to read as much as possible all the while. The tank has cycled and parameters (I'm checking ammonia, nitrites, nitrates, ph, salinity, temp) are in check. No fish in the tank. I left a sponge filter in the sump for a week and then put it in the filter for a 10g QT tank. The QT tank has a crappy filter, heater, and ammonia alert card. The filter water is about 2" waterfall so it is agitating the water. Filled with water from DT tank. Went to the store and bought a pair of clowns. Got them home and drip acclimated to tank salinity and put them in the QT tank. I didn't measure the salinity of the water they were in, but it was much lower than my tank (which is 35ppt). One of the two didn't look so great, a bit dull coloring, which she kinda had at the store too (maybe a red flag). Neither would eat in the QT, figured too much stress. Next day, dull looking one is keeping her mouth open, which didn't seem good. I tried to feed again using pellets, flakes, and frozen mysis and neither would eat. Did a 20% water change in the DT that night and vacuumed up the uneaten food. Next day, dull one has got some white stuff showing on face/gill plate and not looking good at all. Still mouth open looking like she was gasping. Wasn't sure what to do so I picked up Cupramine that day and dosed at night. Followed their directions of half dose to start because it didn't seem like the fish was going to last long if I stretched out the timeframe to add it as I saw recommended on here. That was last night. This morning she didn't look like she would make it, and sure enough when I got home from work she had passed. I feel bad that I wasn't better equipped/educated to deal with this. Now the other clown is still in QT. He had seemed OK (at least compared to the other one), but still not eating. And today when I got home from work I see that he has a long stringy poop coming out, which I now see could be a parasite which would not be treated by the Cupramine. That's where I'm at right now....no idea how to proceed. The seachem instructions say not to mix medications. Plus there's only a half dose of Cupramine in there at the moment (Seachem says to add the 2nd half after 48hrs, which would be tomorrow night). So do I do a full reset in the QT tank (100% water change and rinse everything) and then medicate this guy with something else? I saw a few of the medications are to be ingested, but this guy isn't eating. Thanks in advance for your help.