what size sump?`

[JasonJ]

due to the dimensions of my 70gal cube tank. (30 x 30 x18)

i need a sump that will fit under it.
i was thinking a 20 - 25...i dunno if it will be big enough?

i have a 33gal..but its 36inch long. its not an option.
any ideas? i will be using a ER RS135 protein skimmer.

[SeaHorse_Fanatic]

A 27g tall is 30" long or a 25g tall is 24" long. I would personally prefer the 30" long sump. Bigger is better when it comes to sumps.

[BCOrchidGuy]

To figure the size of sump you NEED simply multiply your dimensions by how much water you plan on having drain off the surface IE, if your tank is 30x30 and you want to drain 2 inches off the surface into the sump then you'll need 30x30x2 = 1800 then divide that by 231 = 7.79 gallons. Now to allow room for your equipment you may want to go to a larger tank for your sump but you have a lot of choices now.

Doug