confused about sumps and refugium set up

[Scubaman]

I'm planning to set up a sump or refugium but I can't figure out the pump I'm supposed to use. How do you balance the water falling in and going out. If the pump is to strong, the sump/refugium will be emptied and if it's to weak it will flood. The rim of my tank is about 45 inches off the ground and it is a 55 gallon (48x12x18). Also, what diameter tubing should be used and such and if I hard pipe it all, how do I glue the pipe together?
Thanks for your help.

[reeferdude]

The siphon you have to bring the water in the refugium should take care of this. If the siphon flow rate is larger than the pump flow rate you should not have a problem. I will try to get pics of mine up soon. The refugium I designed and I use that word loosely is very "home made". I took 2 collection boxes (the ones the LFS uses to catch fish) and drilled holes along the middle where I wanted the water level to be. Then I hung one in my sump and one in the refugium. The refugium is slightly lower than the sump in order for the siphon to work correctly and not break if power is cut. Then I took a 3/4 inch hose for the actual siphon between the two. I have a small pump in the fuge that returns the water back in the main tank.

[TheDogofWar]

I'm planning to set up a sump or refugium but I can't figure out the pump I'm supposed to use. How do you balance the water falling in and going out. If the pump is to strong, the sump/refugium will be emptied and if it's to weak it will flood. The rim of my tank is about 45 inches off the ground and it is a 55 gallon (48x12x18). Also, what diameter tubing should be used and such and if I hard pipe it all, how do I glue the pipe together?
Thanks for your help.
maybe you already found your answer but if not, you have to realize exactly how an overflow works. It's complete physics. 2 bodies of water connected via siphon will seek equillibrium. In english, 2 buckets of water connected by an airline filled with water will lvl out the same.

This is how an overflow works, there is an internal and an external box (your 2 bodies of water) They are connected by a siphon tube. w/o flow, the two bodies will seek the same lvl as eachother. I find it easier to think of the siphon tube as more of an equalizer than a siphon and doesn't flow at max capacity. If it does, your in trouble.

I'm not so good at explaining so I'll leave it at that. heres a couple links that should fill in for me :?

http://www.melevsreef.com/what_sump.html
http://www.cyberreefguru.com/general/overflow/overflow.html
http://reefkeeping.com/issues/2003-01/gt/index.htm

[Scubaman]

great links, thanks.
Do you know if the glue used for pvc pipe is safe to use for the plumbing, or do I need special glue?

[TheDogofWar]

great links, thanks.
Do you know if the glue used for pvc pipe is safe to use for the plumbing, or do I need special glue?

It's fine, just make sure it's fully dried before you put it to use.

Some ppl use it within minutes of drying, myself I wait 24hrs while I let it soak in water. The smell is gone after this and I feel much more comfortable about it.