simple drain holes vs internal overflow box

snake

New member
Hello guys, i'm in the process of making a new glass aquarium, but I can not decide which overflow system is better, I used to have an acrilyc hang on overlflow box, but it is always a pain when the syphon breaks.

So my question is

What works better and why?

1.- A simple drilled hole (with a trap) in one of the walls of the tank
or
2.- An overflow box build inside the tank


please advice with some pictures if you can.


Thanks
 
I think an overflow box built into the tank looks much more "professional" and really makes the tank look good. The drains on the back wall look cheap and reminds me of standing in a fish store, JMO!
 
<a href=showthread.php?s=&postid=7804193#post7804193 target=_blank>Originally posted</a> by daytonians
If you are actually making a glass aquarium, I would go with a calflo style, external overflow.


thanks, i don't know the calfo's overflow could you post a link or a picture of that ?
 
I built my box in the tank, and drilled the tank for a more professional look. I also used BLACK glass - again for a professional look.

If you BUILD A BOX, yet still run a siphon cane over the side... why waste your time...

Thats why I also drilled bulkheads for all my returns as well, but don't forget check valves if you do this.

Jason
 
Both will allow water (of any flow rate) to enter the sump. The major reason people use an overflow box is better surface skimming. Actually for a given flow rate the box with a larger perimiter will skim better than one with a smaller one. That is because the water streaming over is in a thinner sheet. Most of the gunk goes right to the surface and is a very thin sheet on top of the water. This is the most valuable water to send to the sump and skimmer.

Some people argue that not having teeth on a overflow box is an advantage for the same reason. The deepest part of the teeth is pulling water 1/2 inch below the surface and not pulling any of this surface junk. They use other means to keep the critters from getting in the box (egg crate, sponge, screens, etc)

Now I agree that surface skimming is important, but at some point even if you aren't pulling only the tiniest layer of water off the top, you will pull enough to keep anything from building up.

Obviously the disadvantage of a box is it takes up either tank space or room behind the aquarium(for an external overflow) which you might not have.

That's my $0.02

I really like this guys idea for an overflow, only I would drill the tank. Its especially fetching and blends in perfectly if you have a black background. It's also not too big, a nice tradeoff for reasonble skimming without a large sized box. Nice asthetics.

http://www.reefcentral.com/forums/showthread.php?s=&threadid=894704
 
<a href=showthread.php?s=&postid=7804193#post7804193 target=_blank>Originally posted</a> by daytonians
If you are actually making a glass aquarium, I would go with a calflo style, external overflow.

The Calfo style overflow is an internal overflow box.
 
Well I decided a 1 1/2 " bulkhead at 1 inch from the top edge, and built a small overflow box inside, that works awsome and it is absolutely quiet no need of durso devices. I will post a picture later.
 
CoolUser,

the teeth also cut down on the linear distance.

The teeth are a waste of time and serve no purpose other than eye candy. They reduce the effectiveness of the overlfow.
 
Yeah my current 100 gal has teeth on the overflow. I bought a sleeper goby last week. The next morning he was in the sump refugium. So it doesn't do too well at keeping the critters out either.
 
Here is mine

Here is mine

Well this is my overflow box looks much better than a simple hole for the bulkhead


x1poX_nVzrJvrcUP9ORSNQi4fK7IxGG3YmwecGzFs2eOGnN5k7N0Sq-0AF3omQVS0DoCRguWTa-MVfBVVR5Nma0Lro6snCFl4_-CQcCaUU5o2sbJSUIXKqDM5AD6VssMW2x_1ttKYvpIsM
 
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