Beananmial overflow height

[cbrogdon]

I'm sure this is posted somewhere but I can't seem to find the answers or I'm finding several different answers.

Setting up 260 gallon reef tank with cost to coast overflow down 1" from top of tank. Doing beananmial overflow that will come up thru the bottom of the overflow not the back of it.

Are the main siphon and secondary siphon same height?
How far down do my elbows go from the top of coast to coast overflow?

[mcgyvr]

Yes open and full channels are the same height.. emergency too (just elbow turned up instead of down)..
Exit of pipes (in the sump) need to be a maximum of 1" below the water level to avoid starting issues,etc...

As to where elbows/bulkheads go vertically there is a minimum distance from top of glass to top of drilled bulkhead hole (don't remember off hand but want to say a min of 1.5x hole diameter) to avoid cracking/stress.

Its really about making a pencil drawing (to scale) of the specific fittings you've got and setting your desired tank water level and setting the top of the c2c below that level.. mocking up how the elbows will sit,etc.. top of elbow should be below the top lip of the c2c.. emergency height to obviously save you from a flood,etc.
Then building the c2c and laying out the holes based on all that.. Time to bust out the tape measure/pencil/paper for the specifics of what you have..

There is a huge thread in the DIY section covering EVERYTHING you would ever know..
Starts here..
http://reefcentral.com/forums/showthread.php?t=1310585

[cbrogdon]

All of my holes are already drilled up thru the bottom of the overflow box so I'm assuming that the emergency over flow will be not have an elbow on it since I'm coming up and not in from the back?

Thanks for the link to the thread somehow I missed that thread.

[mcgyvr]

yeah you don't need an elbow on the emergency if coming up from the bottom..