mofo....make that tank barebottom...I just took all the gravel outta mine and it allows them to get to all the food easier(pellets) and makes cleaning it and keeping it clean much easier....and it looks cool. But nice setup....I love the mouths on these cats.
I have 3 gulpers in a 75 gallon (4' x 18" footprint) 1 xp3, 1 aquaclear 110, 1 300 gph powerhead, 1 hydor korelia 4) I check the water parameters everyother day and it is fine for about a week and a half and then I always do a 60% or more water change. Just be sure to get an API water tester(ammonia, nitrate/nitrite, ph). Also test your tap water just to see where it is.
They do not need much room I think you can get away with 3 gulpers in a 50 gallon breeder. Mine all ways in one spot. I am going to get 2 more gulpers later. The important thing is to over filter, because when they take a dump it is nasty!!!! Mine even fart sometimes (I see alot bubbles comming out of there butt) I will also be adding more driftwood. I like the two tone mopani wood. I will just wait till i find some for cheaper right now.