I have a megaflow sump model 4 (rated up to 240g) with a Danner mag drive 18 on a 55g tank. this is my growout tank. fish seen to love it. The only reason I'm using such a large set up is I had this just sitting in the garage so I figured why not.
ac 110 and 250 power head on a 29gallon. 25 times an hour
125 with a marineland c-360 rena xp4 2 350 gph powerheads and a pos hob that does 250 gph. 14 times an hour
2x ac110 --- 500gph
1x 100g instant ocean protein skimmer --- 295gph
1x eheim 2213 --- 116gph
live rock --- however much water is flowing over it... lol
I got a 55 with a top fin 60 an eheim 2215 and an undergravel air powered. Powerheads are here just waiting for install with two extra lift tubes run with the same powerful air stones
This is the filter system for my Piranha tank (84L X 24D X 20W inches).
First tank is a prefilter. starting with Jap mat then 3 courses of sponge and a filter wool pad. From this tank most of the water goes into third tank, which is full of bio-balls. but some is pumped into second tank via a 30 Watt UV filter.
second tank is empty at the minute, apart from the heaters. this tank filters into third tank also.
In the bottom tank has more filter wool, carbon filter. and also pumps water into a homemade dry filter full of jap matting, the water is pass through a sprinkler above the matting.
here some picture to help
First and second tank are 24x15x12 inches.(LxDxW) Third is 30x18x12. Bottom tank is 51x19x19.
I'm now planning on changing a couple of thinks in this filter, to make it better.