Wolf I like some of the points that you make, but the only real danger I can see in overfeeding them is the fact that they might become overwieght, or get sick in the water leading to nightmares in tank maintanence. In the wild these fish are opportunistic. Their bellies expand for a reason. They gorge themselves and then have a fasting period. If something happens to come along while they are fasting they will still try to eat it, it's all part of survivability. I have no doubt in my mind that there is or was once a rtc that is over the 6ft mark. I recently read a report of some freshwater biologist here in montana that were doing an electro fishing survey of sturgeon populations here. They came across a channel catfish that was in their estimate around 5ft long, and couldn't be fit into their sturgeon survey net. Funny thing is that the state record here was around 28 lbs. and the world record is around 58 lbs. they estimated this fist over 80 lbs. Not saying that anyone has a rtc that will get to over 6ft in their aquariums, but I have no doubt that with modern advances in the hobby someone will have one over 4ft. in the comming years. Look at the wells catfish many legends report this fish 800-1000 lbs. and over 18ft. long. Largest ones being found today are in the 200-250 lbs. mark. These catfish all have the potential to get huge, but over fishing won't allow it because it takes such a long time for them to reach that size. I say if you can keep a rtc alive for 50 years and feed it properly you might just have yourself a 4 ft.+ specimen. Remeber also they need a varied diet. You can't expect them to get huge off of goldfish, or fish alone, in the wild disections have shown they eat mainly invertebrates, and smaller fish, plus fruits. You want a really healthy rtc, start feeding yours, bananas, pieces of apple, orange, shrimp, whole lean fish, ect. Don't feed them garbage that they can't digest. Again everything stated is from personal expirience and from tons of research, and shared conversations with naturalists, and freshwater biologists. Just to site one more account, the current blue catfish world record is around 124 lbs. I believe, they are caught in nets over 150 lbs every year, and mark twain brought three over 200 lbs., and one over 300 lbs. back to a museum in the 1800s. No telling how long these giants can live for in proper conditions. Be nice to see private aquariums with 4-5 footers in the future. I've read an article where they use the rings in the pectorial spines of catfish to determin age much like the rings in a tree. They counted the rings in a rtc that was close to 5 ft, and wieghed 125 lbs. They said it was estimated at 41 years old. I'll try to find some of the references when I get home.