Join Date: Oct 2010
Location: Victoria, Australia
I think it all depends on the individual fish itself, as well as a combination of its genetics and its prior/current care. I'll use my fish as an example.
All of my fish are treated the same. I am fastidious with water changes, and make sure my water parameters never shift to harmful levels (which means 0 ammonia and 0 nitrite at all times). All my fish are fed the same diet on which 99.9% of my fish are thriving, and all tanks are heated with each fish having a minimum of 3.5 gallons.
However, my only two CT males have both shown serious health problems. One had a problem with his gills/breathing a while back, which although rectified, was followed by some pretty rapid melting of his fins. He now has what looks like a tumour growing on his side, although it has yet to affect his mobility or appetite. He was imported as a pair from Thailand, and aside from a recent bout of bloating (she finally got it all out of her system today), his female counterpart has remained perfectly healthy.
The other CT male who I have had for at least 6 months now, has developed a bent spine and delibitating swim bladder issues. I'm now in the position of deciding whether to euthanize or not since his current standard of living is not what I consider humane.
Oddly enough, the rest of my fish are all healthy and full of life. One of my recently purchased pairs, live in the same tank, and the female was so barred up the other day, she looked like zebra, while the male was alternating between building a bubblenest and showing off for her through the divider.