please help me finsh my sump

[skype]

I need some help partitioning my sump tank. I can't decide how big to make the inside partitions. The sump tank is complete just need to partition it.
here is a drawing of my sump tank.

thanks for any help

this sump is going into my first reef tank. Here is the thread I started a while back.http://www.reefcentral.com/forums/showthread.php?s=&threadid=731551

 

[Siklid]

what is your return pump size + 2" for space around it

so 18.5 - (pump size + 2") - thinkness of matterial ( 1/4" ? )

 

[skype]

siklid,
thanks for your response.
I am planning to use a mag 7 or a mag 9 as the return pump. so having 2" more than the pump is enough room? will this be a good volume for the return section? i will be setting up an auto top off system.

 

[comatose]

the return area is way to small, needs to be bigger, this is one reason i never add the skimmer inside the Refugium, takes up way to much room in the first chamber on these smaller Refug's. the evaporation level goes up and down in the return area, and with that small of a space you'll have water splashing around in no time. even with a auto topoff system, it'll be clicking on and off constantly.