not to be rude but this has been addressed a dozen times in this thread already.
To answer your question though, no, they are not like snappers that have difficulty swimming. In fact they are very adept at it and are commonly found in deep waters. In this tank he has two options for a resting place: on top of the cinder blocks and leaning on the driftwood. He has been in this tank for sometime and is still doing very well.
I keep my yearling Alligator Snapper in a deep water tank and he has no issues swimming in it, he is a much better swimmer than my Musk and Mud turtles at least. They are not the best and they look weird swimming, but my little guy swims through the tank all the time with no issues.
I never said they couldnt swim, just that they have difficulty swimming. Even the babies are clumsy but adult ally snappers swim about as well as a rock.
They are crappy swimmers I'll give you that, mine is kinda of weird in that he will swim to the top of the tank and then kinda of float towards the bottom with his mouth rid open right through the school of minnows. Its so damn freaky looking, especially when he catches one like that.
in regard to any posts concerning the water depth, an aquarium near me has a fully grown mata mata that they've had for 2 years in a 5-6 foot deep aquarium. i have personally seen it both swim to the top to breath and climb the root/pillar in the middle of the tank to breath with no problems whatsoever. please leave the issue alone.