Hi g. Just the same advice as everyone else really. I have 2 in the tank and they will get under everything so 100% on the Avalanche . The posative to this is they keep your sand bed pristine, I added mine last to a well stocked tank, so floor space was at a premium and I have plenty of other burrowing fish, blue spot jawfish, pink spot goby and diamond goby all living in sand bed and they never cross into each other s territory so I think you can keep their burrowing contained to a certain extent. Size wise the one is about 1' 2" currently and the other is around 8" , they were both the same size when they went in about 2" so I can only agree , but have no idea what is happening with all the size variations everyone is talking about , but I do know one thing. They grow fast !