Advantages to internal overflow?

[R Baxley]

I have a 29g right now that is drilled for return and drain, but without the internal overflow box. I used to have a 65g WITH an overflow box. I hated the space that the box wasted, and quite frankly I can't really see much advantage for the internal box...thoughts?

Is the main advantage simply flow rate? For my next tank I am considering going without the internal overflow...thanks for any input!

 

[cjburden]

could do something like this

http://www.reefcentral.com/forums/showthread.php?s=&threadid=380017

 

[scavdog]

Overflow boxes give you the advantage of skimming a larger area of water for procesessing in your sump. Essentially, the larger the internal box the more effectively the water is being skimmed. Surface area rules.

When I do my next "large" system, I hope to use a larger overflow that takes up close to the entire back of the tank. However this will be a custom external built-in overflow and will not be very obtrusive.


hth,
Joe

 

[scavdog]

could do something like this

Very cool.

 

[DanStL]

The other thing to consider is that hang-on overflows can have problems loosing suction, causing floods. There wasn't a fail-safe option when I was looking 6 months ago, that's why I made an internal setup.

 

[R Baxley]

THanks for the input all.

I'll probably just buy an AGA rr tank. i like the new design with the rounded corner overflows. they seem less obtrusive than the rectangular ones.

 

[DanStL]

I made a rounded internal overflow (off-center, not a corner) from a $14 clear acrylic food container. Works great and it was pretty easy to do with a dremel. I am fairly certain this container has enough diameter to work as a corner overflow, if you do the durso-through-the-side-glass type of setup.

 

[Matt L.]

...I hated the space that the box wasted, and quite frankly I can't really see much advantage for the internal box...thoughts?

Is the main advantage simply flow rate? For my next tank I am considering going without the internal overflow...thanks for any input!

There is generally a tradeoff between hydraulic performance and the length of the weir. In the case of our reff tanks, as others have mentioned, the longer the (overflow) weir, the better the skimming and the less likely the chance of a backup and overflow should the flow rate through the tank increase,

Matt

 

[Piscevore]

The wider your over flow, the better, as I understand it, because it allows you to skim more "surface" water, which is where the majority of your nutrients reside?