i had an old 30 gallon acrylic tank laying around so thought it would be fun to set it up in my man cave and purchase a couple of convicts. I've read for years how quickly they will over run a tank with their fry but figured I need to experience it at least once. I set it up with two nice big rock piles and bought a male and a female from Petsmart three days ago. Well, three days ago was the last time I saw them. The second I dropped them in the tank they instantly disappeared into the rocks never to be seen again!