I don't know why but my Axolotl doesn't seem to be growing very fast. He is about 1 and a half inches long, has all his legs and is probably over half a year old. He seems very health and he is very active. I keep him around 20 degrees Celsius and clean his water once or twice a week. He is in food container that I bought just for him so nothing has ever been in it. He has fake plants to hide in and a small cave to hide in although he never uses it. I feed him bloodworms, small worm pieces and he used to eat brine shrimp. He has actually grown a bit since I got him and he has grown his legs since I got him but is just growing so slowly.