Restricting amount of water to return pump

[moorediddy]

Ok, there's one thing that I'm still unclear about in my refugium plans. The section in my fuge/sump for the return pump is baffled off, but how do I limit the amount of water in that section? Is it set by the a mount of total water I put into the section when I'm setting it up (Assuming my overflow from fuge rougly matches the amount being pumped out, it would stay the same)? I'm concerned because I see lots of people with a lot of water in their return section, and I can't imagine the tank holding all of that water if the overflow were to fail or become clogged.

 

 

Also, if that does happen, and the pump pumps out all of the water, what happens to the pump? Do they burn up from running with no water? Or do some have a shut-off valve when they run out of water.

 

 

-moore

[ELGORDOINAVW]

pump will burn out, the water in the return section should have alot of water to prevent the return pump from running dry.