About overflows

[fishingbuddy]

Hey guys,

Just set-up an overflow on my 29 gal. Was wondering, since the water at the top skims off, what about the water at the bottom of the tank. I know it's something that I'm overlooking somehow.
Have 1 mj 1200 and 1 mj 400, with a mag 5 in my sump. Pointing out the obvious would be helpful

Thanks

 

[xrbzq]

Scum (organic waste) collects on the surface of the water. Skim the surface and it goes into the protien skimmer, then collection cup. What problem are you having with the bottom of your tank?

 

[fishingbuddy]

no problem was just wondering about the water "circulation" from top to bottom or bottom to top.

Thanks again