I am currently deciding on whether to get a red wolf fish or around 15 of these little guys, but there are a couple problems. One of these problems is that I have no idea how long they live for. Also, most of the places online that have these guys in stock sell them when they are 4" which I believe is the max length they can reach. Please answer these problems if you can and if you know any sights that sell these guys at about 2"-3", please post it. Thank you. 