NaCl!
Keep it at about .2 percent ( aka 2ppt or 2000 mg/l.)
As you probably know it's not actually used to treat fungus and bacterial infections but it will keep the stress levels down to keep their immune systems up to par.
I've also become a big believer in potassium permanganate at 2 to 4 mg/ for about 4 hours to eliminate gram negative bacteria in the tank and external parasites if fish have problems. Just make sure the biofilter is offline and you start at the low end.
Had some serious bacterial and possible parasite issues with some tilapia I had fedexed overnight recently, and the PP in conjunction with a broad spectrum antibiotic finally did the job. Also briefly increased the salinity significantly. Thanks to Kellen Weissebach for his expert advice. (Fish are not destined for the table).
Last edited by Cecil Baird1; 09/13/15 10:58 PM.
