I have purchased a Nes axo and when I got him he had beautiful frills on the side of his head, I have had him home a week and he will not eat and the frills have disappeared. I have contacted the pet shop I got him form and they advised me to clean the large gravel they gave me and to do a 1/4 water change I have done this. He also pushes himself to the top of the tank and gulps water, the filter is the tank is bigger than the tank requires. I have tested the PH and it is ok and I did make sure the water was de chlorinated, as I lost the last Axo I had I will upload a picture once I have my computer up and running