Sick Fish - Can't solve the problem

[Jaws]

So about a week ago my tank came down with velvet, or at least what looked like velvet. After I added about 30 pounds of live rock from another reefer's tank, all the fish started showing signs of blotchy skin, heavy breathing, and erratic behavior within about 24 hours. They definitely had some kind of parasite so I removed all the fish, placed them in quarantine and treated with chloroquine phosphate about a week and a half ago. They seemed to bounce back pretty quick over the next few days. All looked good and were eating well. Then about 3 days ago all the fish decided to go on a hunger strike. Now some of their fins are starting to deteriorate and they're showing signs of blotchy skin and swimming funny again. Temp is 78, pH is 8.1, NO3 is under 5, PO4 is 0.1 and Alk is 10. I've got power heads pointed up too so there's lots of surface agitation for added oxygen. Am I missing something? I can't stand sitting here and watching them get worse. If anyone has any other suggestions I'm all ears. Thanks.