Hi i was wondering if anyone could help me with some advice as to what i should do with a problem I've been having. Several months ago i set up a 40gallon hex tank. I know the problems Ive heard regarding the need for lots of territory but the tank has a swim through giant rock formation so i thought that this would help solve that. So I originally cycled the tank for about 2 weeks and then added 3 fish from a new lfs(the only available one in the area)(1ice blue zebra, 1 albino scolfioli? and a melanochromis chipokae) and from the start one of the fish appeared sick(chipokae), and it unfortunately died the next day and was able to get a replacement that lasted 2 days... At this point i didn't want to risk buying anymore sick fish from the store, so i would hold off for a while. Since I am away at college i was then able to go home 2 weeks later and collect 4 juvenile QB peacocks and a yellow lab from my tank at my Parents house. I drove them them the 4 hours back to school and put them in the tank immediately because i cant bring a Hospital tank here.. I checked all the water parameters and everything was normal and under control so i thought there would be no harm in this. After 3 days 1 of the fish(M peacock) appeared to have a mouth injury,which was strange because i never saw them any real fighting, so i thought the aloe vera in the stress coat chemical i had would suffice. Nope.. this fish died and then the next day the 2 other died of similar strange deaths. and then the other did 2 days after that. After this i was left with 2 fish that remained fine for the next month with no problems whatsoever. So after convincing myself everything was back in check i decided to buy 3 more fish, 3 melanochromis cyaneorhabos. they all appeared very healthy and in good health so, i brought them back and the next morning i noticed on one of the fishes body right before the tail started, a dark mark that appeared irregular. The fish was still active and healthy so i dismissed it. 2 days later I noticed it turned white and appeared to be fungus so i went to the store and bought PimaFix. I treated it for 7 days and the fungus went down and then reappeared a little on day 5, but not as bad. now its day 8 and all fish are still alive but still a little fungus on the tail. What should I do? I am bewildered at this. Any help is appreciated!