refugium overflow question

[saltynewbie]

hello all-
i have been researching the previous posts for info/ideas for a fuge. is it absolutely necessary to use an overflow or is it possible to just create a siphon in the upside down U style? what are the advantages of using an overflow over the upside down U siphon? thank you for your time!!!

 

[tkblazer]

from what i've read, the overflows are ideal but not the only way to go. a lot of people use the hang one overflows, but the drawback is the possiblilty of that u pipe losing siphon while the pump in the sump/fuge will still pump water possibly overflowing your tank.

 

[cap'n pete]

You can not control the flow from a straight siphon, and therefore will end up with a flood. An overflow can only take water that it is given, so there is no trying to get flows "just right". If you don't want to do an overflow, you could do a gravity fed refugium.