Need help with my 200 gal tank setup

id go with two. it allows more flexibility. and flexibility is the key to survival.

ok, i thought about it and let me clarify. if you really want to figure it, there's formulas used in water engineering to cpute the water flow through a pipe between two reservoirs( in this case, two fish tanks). however, most people can access those equations easily, but would not apply them correctly. if it was me and i had to go this route, id go for two outflows, as i said. yet, i would feel best just figuring out a better way with pvc pipes and a good size water pump. drilling a tank's glass would qeaken it in my opinion, and even though its done lots of times for thousands of tanks with a problem, it would still be a cause of concern.

hope that michmash helps.

Not sure what your question is really asking, are you talking about the intake from your main tank going to your sump? Or the outake from your sump to your tank?

If its the first one since it is a 220 Gal and from your info given im assuming you're only putting 1 hole to your main tank as an intake to your sump. Then i would go with the 2" hole (, also where will this be located in your main tank specifically?

If its the second one well that just all depends on your pump.

Well here is a chart that might help you decide.

Pipe size ...... Gallons Per Hour ........... Gallons Per Minute
½" ........................ 480 ................................... 8
¾" ........................ 900 .................................. 15
1" ........................ 1,500 ................................ 25
1¼" ..................... 2,700 ................................ 45
1½" ..................... 3,600 ................................ 60
2" ........................ 5,400 ................................ 90
3" ....................... 13,500 .............................. 225
4" ....................... 21,000 .............................. 350
6" ....................... 42,000 .............................. 700