center internal overflow on a 300 g?

[tahiti422]

i have 4 pipes in the overflow. do i get 2 standpipes and 2 shorter drains or just 4 standide pipes? and how much flow would i get? any help is appreciated

[tahiti422]

http://i436.photobucket.com/albums/qq87/tahiti422/overflow.jpg

[digitalis]

what size are the bulkhead fittings? are all 4 the same size?
How many GPH do you plan to run at? If you have enough to easily overcome 2 full pipes, it might be ok, but if the siphon really got going, it might toilet-bowl on you. If you did that, I'd leave the two bulkheads just with drain screens over them, no pipes. 2 1.5" pipes should maintain at LEAST 5000 GPH between the two of them. If you are running any less than that, they would fill the pipes, and two of the four would gurgle, or not work at all.
The other thing to consider, is are you planning to run 4 separate drain pipes, or combine them under the tank? If you combine, you can only flow as much as your final output pipe.
Check this page for an idea of flow rates.
http://flexpvc.com/WaterFlowBasedOnPipeSize.shtml
Hope this helps.

[digitalis]

looks to be designed for two returns and two supplies. My AGA was designed that way, but with two separate boxes.

[tahiti422]

yeah all four are the same size

[das75]

once you know the drain size work backwards from here http://www.reefcentral.com/calc/drain.php

[tahiti422]

all four are 1". so should I use all four or drill 2 holes for 1.5"? and how much flow is 4 1" bulkheads?

[indydog1]

600 gph per 1 inch bulkhead.

[tahiti422]

o good thanks so how do i do that with 4 standpipes? or 2 standpipes and 2 pipes?

[das75]

If you have two drains available (assuming the others will be used as returns) and noise is a concern, should consider a classic Herbie. Totally silent.