10 Gallon planted "quarantine" tank with 3 amano shrimp, 3 painted platies, various snails, and 3 small neon tetras that I was planning on adding to a 15 gallon tank with 6 other neons. After about 2 weeks I started to notice one of the neons started to get a white bump on the side of it's mouth and another looked to have some white on the top part of its tail. I then dosed the tank with API melafix and pimafix according to instructions (daily for 7 days, then 25% water change). During treatment, it looked like the growth on the mouth had been slowly growing, to the point I could definitely tell it had gotten bigger by the end of the treatment. I proceeded to treat the tank with API E.M. erythromycin according to the directions (one packet, wait 24 hours, add another packet, wait 24 hours, 25% water change, repeat, then add carbon). It's only been a day since end of treatment, and I have not seen any decrease in the growth or the fin getting better. I'm just worried that if it is Neon Tetra Disease, that it could affect the third neon. Any recommendations would be great. I've been thinking about setting up a true 10 gallon quarantine tank with just a seasoned sponge filter and no live plants, then trying aquarium salt. Thanks in advance!
pH - 7 to 7.2
Nitrates - 40 ppm
Hardness - gh 150 ppm
Nitrite - 0
Ammonia - 0
KH/Buffer - 40 ppm
Water Temperature - 75 F
