In the time I've been breeding and growing out angelfish, I've found that wilds are much more sensitive to medications and salt.
The most important first step is to verify that is a fungus, columnaris sp. can have quick deadly effects and is actually a bacteria. My experience tells me that being a newly aquired and wild strain of angels it is probably a combination of problems, possibly secondary infections are a problem as well.
Go very easy on the salt with these guys, I wouldn't do a standard dosing unless it was for less than 15 minutes, might even only do a short term dip in a bucket (5-10 minutes in a mixture of 1-2 teaspoons per 5 gallons.
If you are looking at adding salt to the tank, do it in much lower quantities than the 1 Tablespoon to 10 gallon guideline, possibly start with one teaspoon per 10 gals and the next day add a second teaspoon and stopping there, followed up by a water change on the 3rd day. Remember there are 3 teaspoons to 1 tablespoon.
Melafix does wonders with clearing up miscellaneous true fungii and helps as a mild antiseptic. Greenex is another good additive for preventing the spread of fungii.
Also, do you see any fin deteroration or damage? Make sure you don't have a secondary infection of finrot or something, as that is something I commmonly see in imported wilds.
Keep us posted.
Regards,
Raithan O. Ellis
