I am using a pen play 100 gallon canister filter with biomedia in it and will install an undergravel filter as well as I heard frontosa will breed later on in life if they have an undergravel.I've never had a tank this big before.Right now they are all juveniles in a 72 gallon bow front using the same filtration.
I am putting in or hoping to put in all my fish in the 125 gallon.I have 7 frontosa,3 clown loaches,4 blue dolphins,1 yellow lab,1 peacock,1 high fin spotted pleco,4 silver dollars ( which I may not keep as they get large in size as well).They are all juveniles right now.The undergravel will be conventional with 6 vaccum tube across them.I know undergravel aren't recommended but they seem ok with one now.I am also using tan and brown colored gravel and plan to decorate the tank lightly for maximum room.