I noticed on the same day that both Shiny and Fishie have fin rot.
They're in separate tanks, and Fishie's tank is filtered and cycled. Why did they both get it at the same time and why did Fishie get it in a cycled tank? He was in a hospital tank until a couple of weeks ago because he had been biting his tail. It was beginning to grow back, so I put him back in the 5 gallon and now he has fin rot.
I change the water in the 2.5 twice a week- one 75% and one 50% change with a gravel vac (the water from his tank always smells really gross, though). In the 5 gallon I change 25%-30% of the water once a week. I tested it, and there is no ammonia. I haven't tested nitrites in a while, and I never tested nitrates because my test kit didn't come with it.
Is it because I use the same bucket to refill both tanks so the bacteria got into both tanks??
I feel like a bad fish mommy.
I'm treating with aquarium salt, Stress Coat, and dried oak leaves I gathered from my parents' yard. Is this treatment ok? Shiny's dorsal fin does look better than it did two days ago- the red edges are almost gone and the hole is smaller.
But why did they both get it at the same time?