Hey everybody, I’m writing this post because I am very lost and am looking for some guidance and or advice. I’ve been keeping fish for close to a year now with honestly pretty good success, I struggled at first, mainly because I didn’t know what cycling a tank meant, but now I’ve got a 10 gallon and a 55 gallon tank that have been running over 8 months with residents. Currently the problem I’m having has mainly been in my 55 gallon. In the tank I keep corys, danios, plecos, and honey gouramis, plus one angelfish. I have 4 species of corys, panda, peppered, albino bronze, and corydoras undulatus. In the past few months, I’ve had a surge in fish sickness, and I don’t know why. I lost one of my panda corys and one of my albino bronzes within a week of each other (just died without symptoms), and then all was well for a while. I noticed one of my 3 corydoras undulatus had a fuzzy spot near his mouth, and so I moved him to a hospital tank, and began treating him with rid ich and supratect as recommended by a reliable discord group (it’s very difficult to get many reliable medicines for fish as I live in Ontario and many of them are controlled substances). It seems to have responded well to the medication, receding from his mouth entirely, and then the next morning I found him dead in the hospital tank. Next, I had a honey gourami contract a similar fungal infection, but in the gills. Transferred to the hospital and began the same treatment, responded well and was okay, returned back to the tank after a week, no symptoms since. Now, in the past week, my last 2 corydoras undulatus have both contracted a fungal infection. One I transferred to the hospital, and had the same result as the first cory, and today I just noticed the same for the last remaining cory. To give everybody a bit of an idea of my tank situation I’ll add a picture, I’ve got lots of floating plants along with some Amazon swords and Java ferns. I’ve got rounded gravel on the bottom, an aqua clear 50 filter, and a heater that has a built in temperature. I test my water every month, but more more recently because of the sickness. Every time my ph is between 7.2-7.4, Ammonia is 0ppm, nitrite is 0ppm, and my nitrates is never higher than 20ppm. I gravel vac every week, as my pleco makes a lot of poop, and do 30% water change weekly. I feed a mix of omega one pellets, tetra colour boost flakes, frozen bloodworms, and tetra algae wafers once a day and they always eat all the food very quickly. To answer some potential questions right off the bat, I never noticed any barbel damage on the corys that got sick, and my hospital tank is/was cycled with extra filter material from my tank. I also included a picture of the first sick cory I found. Any help or advice is appreciated, I just want to know what is happening or I might be doing wrong.
