I'm looking to go to the bigger tank. let me know if the larger one with that plastic strap is still available (Very first pic) I have a 4 inch blue crayfish that is in a much smaller tank right now cause he went on an overnight killing spree. my first alert was the shriek from my son as he found crabby in his cave surrounded by 5 other fish...all his 'meals'. greedy lil sob. but he's cool. needs a much larger tank.