hey all I purchased two 2 inch red tailed prochilodus (flagtails) about a month ago. They were in my 80 gallon with a school of adult giant danios and adult teardrop barbs. One died after a week in quaranteen the other lasted about 3 weeks in the 80 gallon now I found it dead when I did a water change, I think the giant danios is the culprit. I purchased 4 inch one online and he came in with ich. I had a large 11 inch that I had for years and he was bullet proof. Are these fish just real sensitive when smaller?