I've had one crab since he was a small in my first 10 gal. I came home one day from school and he was sitting on top of the tank as if to greet me "Hi! welcome back from school!"

After that i started duck taping the lid shut. A few months later i got my 45 gallon and moved him in and continued to tape the lid shut. Now this crab is a large and hasn't grown out of attempting escaped. I had only one piece of duck tape the first time it happened in the 45. He pushed so hard on the lid the tape unpeeled it self. Then I started doing 3 pieces of tape. He eventually grew too strong for that too. Now I'm using this super strength velcro stuff, but I don't think it will last much longer. Once he figures that out i'll probably use a c-clamp. Its always been the same crab too.
btw I've only been crabbing for 6 years and my small grew into a large already. is that a normal rate of growth? its seems really fast.