help, answer needed fast... pre drilled single or duel over flow boxs whats the diffrants and why

[hummer]

I'm looking at a new tank ...an aqueon megaflow 120 gal 2 over flow boxes pre drilled for$550.oo out the door.
my question is they sell a single corner over flow and a duel over flows. what's the difference?

...I'm making a reef tank what's the advantages to the duel over flows?

 

[reefndude]

The ability to move more water. Disadvantage is it takes up more real.estate

 

[DFW]

2 overflows provides more skimming function, and also probably a return line at each end of the tank instead of just at one end. It also uses up more space in your tank. I think that normally if there is only one overflow it is placed in the middle of the tank, although on a peninsula style tank it will be on the end, so it is not an absolute that you have to have 2 overflows, or one in the middle if there is only one overflow. I have seen a 330 gallon peninsula tank with overflow, and returns at one end.

 

[mfinn]

As stated, the ability to have more surface skimming area, and one reason I think is really important. With 2 drains you have less chance to end up with a snail or algae plugging up a drain and causing a water overflow.