Twenty-five years ago I wrote an article on mantis shrimp for Scientific American in which I describe an Odontodactylus scyllarus breaking an aquarium in my office. That story about a very large stomatopod breaking a glass tank has become a legend. Yes, even a small 5 cm gonodactylid can chip the edge of a glass aquaium and cause a leak, but they almost never do. I have over 50 aquarium up and running in my lab, most made out of simple window glass, and we haven't had a smashed tank in several years. If the animals have a good burrow in which to hide, they almost never break glass (unless you have seen "Fastest Claw in the West" which I helped film). So if you want a mantis shrimp and have a decent glass tank, don't worry about it. The chances are you won't ruin the floor! I have had problems, however, with glass heaters. O. scyllarus will attchk and break them either when they see the light come on or when they touch the hot glass. Hope this clears up some misconceptions.