125gal How do I add an overflow?

[Leo73173]

I have a 125 tank that I want to drill and put in an overflow. I want the overflow to be in the center of the tank. What I want to know is what size holes to drill and what sive over flow. Also what size pump shpuld I use to accomodate this setup. Any help is appreciated. Thanks

[xenon]

always drill for two overflows. That way if one clogs up the other can drain. Otherwise your pump will overflow your tank and it will flood your house.

[staticx]

make two overflow drill 2 inch holes and get a 4000 gph return pump

[bracebldrs]

theres a high end lfs by me that drills tanks ,he's now drilling
on top end bout 2in down frow disired water ht , a series of
holes in line .some get 90's with strainer that you angle .aqain
to desired level and other holes get those eyeball outlets you
see on pool or jet tub .plus a water change hole in back with
valve again at level desired .its an awsome clean look.no boxes!!
next tank im doing that .unless any body can show me any thing
bad about it.

[bracebldrs]

as for pump size,look up pump to buy online
they show chart/head loss and go alittle over your
tank gph out put .you can put a ball valve to throttle up or down
on both ends to dial in.10x turnover is the starting point 40 to 50
seems to be average for reef.

[Home_Depot]

I just drilled my 75 and I used 1 1/2 bulkheads and for the overflows I used I think it was 8 in. PVC and cut them in half and put some slots with a table saw siliconed them in the corners works great

[loves saltwater]

What kind of drill bit is used and where can I find one.I just bought used 55 and want to add a diy overflow...I have seen the information on here before but the search will not work.

[brackishdude]

http://reefcentral.com/forums/showthread.php?s=&threadid=619976

[rivdog]

4000gph???

[staticx]

did i say 4000 my bad must have been thinking about something else. Just get one to create the amount of flow you want in your sump. Add the ball valves like previosly stated to adjust your water flow