help me get my cory all better!

[crimsonmoon]

I got three cories from petland almost exactly one week ago, and usually their stock at this location is very healthy, but these three i don't think are. well, two, now. i got two emerald green cories and one rabauti cory, they had been in quarantine for 7 days when one of the emeralds turned very pale. the next day he died. now the rabauti has a white mark on the right side of his head. it almost looks like he's rubbed it on something so much that its gone raw. but idk, would it be an infection?
i think they are depressed from being in quarantine. they never move really, im trying to hurry up and get them healthy so i can put them with all the other cories and they can be happy, but im not going to do that until im sure they're ok. its hard to tell if they're ok by their behaviour when they are in such a small group like this. what do you think? what do i need to do?

 

[ksane]

I treat all new quarrantined fish with 2 rounds of PraziPro (General Cure/Parasite clear is the same thing). The PetsMart I go to has a non-stop problem with Gill Flukes and it clears that up. Make sure your water quality is good with testing. (NOT the paper strips).

 

[pinkertd]

And build their strength up with some frozen bloodworms while they are in QT. It is one of the all time favorite cory foods!

 

[inkyjenn]

they are sitting still either because your water is poor or from illness (or a combination). even in qt, they should be active. do check your water parameters with a liquid test kit. and photos of the cories would also be helpful