Calfo Style Overflow boxes
- Thread starter Jeremy Blaze
- Start date
causeofhim
New member
I just ordered my glass for mine. I'm doing 2" x 6".
BeanAnimal
Premium Member
I think some of you guys are missing the point of this style of overflow. Instead of a "box" you should build a shelf the length of the back of the tank (or as long as possible).
The idea is to maximize the linear overflow length and make the sheet of water as thin as possible. This will greatly improve the surface skimming, quite down the waterfall (make it silent) AND prevent critters from going over the falls WITHOUT resorting to teeth or slots. In addition the overlfow shelf is more astheticaly pleasing than a "box" or "boxes" attached to the back side of the tank. You can add a ledge to attach frags to, this will help hide the entire thing.
Bean
The idea is to maximize the linear overflow length and make the sheet of water as thin as possible. This will greatly improve the surface skimming, quite down the waterfall (make it silent) AND prevent critters from going over the falls WITHOUT resorting to teeth or slots. In addition the overlfow shelf is more astheticaly pleasing than a "box" or "boxes" attached to the back side of the tank. You can add a ledge to attach frags to, this will help hide the entire thing.
Bean
BeanAnimal
Premium Member
Let me also make another suggestion. If you add an extra hole as an emergency drain, you can then tune the overflow to be totaly silent WITHOUT fiddling with a somewhat quiet durso or stockman. The downturned elbows are great for keeping snails out of the rplumbing. If you make them so that they are about 3/8 off the bottom of the overflow box then nothing but itty bitty stuff can get in but you are still leaving enough room to allow full flow.
If you plan on pushing the overflow hard, then you will need the elbows, otherwise you will get sloshing and gurgling as with any other drain. Extra holes/bulkheads will prevent this, but of course you are then not using your resources efficiently in regards to drain capacity.
My snails frequent my overflow shelf and keep it spotless. Coraline is growing in it also.
You can find smoked or black glass and have it cut at any reputable glass supplier. This may be more suitable for some peoples tastes.
If you plan on pushing the overflow hard, then you will need the elbows, otherwise you will get sloshing and gurgling as with any other drain. Extra holes/bulkheads will prevent this, but of course you are then not using your resources efficiently in regards to drain capacity.
My snails frequent my overflow shelf and keep it spotless. Coraline is growing in it also.
You can find smoked or black glass and have it cut at any reputable glass supplier. This may be more suitable for some peoples tastes.
BeanAnimal
Premium Member
I guess I should have been more specific. I prefer an overflow that is the length of the back of the tank, attached to both sides. The "shelf" would consist of a bottom and a front, the tank sides serve as the ends. A differintiated that from a "box" that has a bottom, front, and two sides; the box not being as long as the tanks back dimension and therefore having to be closed by means of end pieces.
In other words, the longer the better, and you can't get longer or easier than the length of the tank.
In other words, the longer the better, and you can't get longer or easier than the length of the tank.
Benny Z
In Memoriam
i'm planning to do this with an 80" long 200g tank that i'm setting up.
should i try to make a jig to "fence" the top of it or should i just glue egg crate across the top and have a flat top'd overflow?
also, about how much flow do i need to keep a steady thin bead of water flowing over an overflow this long? i was thinking about 1000 gph.
input appreciated.
thanks!
should i try to make a jig to "fence" the top of it or should i just glue egg crate across the top and have a flat top'd overflow?
also, about how much flow do i need to keep a steady thin bead of water flowing over an overflow this long? i was thinking about 1000 gph.
input appreciated.
thanks!
BeanAnimal
Premium Member
1000 gph over an 80" long overflow will provide a super thin film of waterr. You surely will not need teeth of any kind. I put 1500gph over a 48" overlfow and don't need teeth or any other means to prevent critters from getting in the overflow.
Bemmer
Premium Member
That size overflow shelf may have to be custom made. More than likely it will be cut into two pieces for shipping purposes. I am having one built by Scott, owner of Aquatic Systems Design in Kansas. He is great to work with. His customer service is excellent. And we are "talking" through the overflow shelf and the sump that he is building for me...including schematics for the design. I highly recommend his work.
Rebecca
Rebecca
Jeremy Blaze
Former Reef Addict
Acrylic comes in 4x8 sheets. Find a supplyer and ask for a 96"x12 sheet. That will give you enough to build it.
BeanAnimal
Premium Member
If it is a glass tank, I would use a glass overflow....
causeofhim
New member
I completly agree.
Glass is much cheaper also. I get mine custom cut for me at a local glass shop and it's very inexpensive. I just had (2) 3/8" pieces cut for me. Both were 23 7/8" and one was 2" and the other was 6". It only cost me $7.88.
BeanAnimal
Premium Member
Benny... smoked or black should not be hard to come by. Most local sign shops will have it. It does not have to be thick, as the water depthwill only be a few inches. You may want to incorperate 2 or3 1" wide braces along the length. I would black these BELOW the lip, at the proposed water level (or below). This will keep them submerged and prevent water from spilling over them and drippin into the overlfow box.
