I have read that the korallin's are pretty much setup and forget but I have never had one, I just got a geo cause everyone is raving about them so figured i will go for it.
I am waiting for my ph controller to get here and setup the geo, from what i can tell it is not hard to setup...One line in...one line out but I am not sure if all are like that or not? This is my 1st reactor.
Good luck!