I have 5 biota tangs that I got 6 or 7 months ago. 3 of them have had raggedy fins and now 2 of them have red soars on them. On a couple of them you can see their veins in certain spots. I dosed with kanaplex 2 doses and it is getting worse. Just started metroplex through their pellets and furan 2, stopping kanaplex as it is clearly not working. Any advice on how to save them would be appreciated. Water parameters are all great.