55 right now. I'm going to upgrade to a 75 before I get them and then I'll have a 40 breeder sump and skimmer. I've just got 2 HOB's right now filled with LR on the 55. Not near enough filtration for one eel, let alone two, IMO.
I've been researching these guys for weeks but so little is known about them and there's only like 4 websites out there that even have any useful info. lol. Never have too much data before spending the time and money, right?