I think you're doing all of the right stuff. If you need more antibiotics, you can get them online without a prescription.
http://www.fishmoxfishflex.com/index.php/fish-antibiotics/cephalexin-keflex-fish-antibiotics.html
http://www.fishmoxfishflex.com/index.php/fish-antibiotics/cephalexin-keflex-fish-antibiotics.html