Johnptc has a 4ft, 4 year old albino channel cat in his 10,000 gallon tank. Thats an average of 1" p/month.
Although a channel cat would grow much faster then 1" a month in its first year then grow slower for the rest.
i once had a little 3 incher that in 6 months was 12 inches, gave him to a buddy to start his pond. unless you have a pond or a huge tank or know someone that does that will take him this is not a great fish for a 55 or 125. you can grow them out in one but long term he will need much more.
mike
I have one in a pond in the garden they grow a lot slower in cold water my one is 4 years old and 2 foot long they grow very fast if the temp is over 15c.
Warmer temps and frequent high protein feedings yield the biggest fish. 3-7 times a week at 80-85 degrees can get you a three footer in 3-5 years. Anything bigger is an awesome specimen. I usually put them in my pond when they get about 14 inches. I have one that is 14 inches right now and I will keep him for another year or so in the tank. vvv r