acrylic tank calfo overflow

[bryanth73]

I am looking at a new 180 to replace the old one. I want to do a calfo external overflow. The tank would be 1/2 in acrylic 72x24x24 with an overflow across the back 12 in deep and 6 in wide can this be done? and anyone know any GOOD places to order? I tried one place but he wouldn't do it, saying the overflow comprimises the tank unless I make it the full depth of the tank, making the tank 72x30x24. I do not want to rebuild stands and have seen pics of the overflows and none were the complete backwall of the tank.

 

[hansnfrans]

Please tell me where you have seen the a drawing/pic of this type of overflow. According to his "Book of Coral Propagation" he talks about building this overflow within the tank. I plan on doing the in-tank version but am curious as to the design of the outside-tank version of this. Thanks.

 

[MadTownMax]

I've seen this done w/ glass - but I don't know where I'd look for pictures - it was in one of the original "drill your tank w/ a dremel" threads, where the guy cut the trim of his tank, then cut slots in the top edge of the rear glass panel of his tank, and then used silicone to put an extra glass overflow box on the back of his tank. This maximizes the usable space in your tank......

bryanth - could you add some supports (triangle-style) under the box to make the builder more comfortable? that should alleviate any worries he has about the seams pulling apart -( the extra worry comes from the weight of the water pulling the top seam off - it was something I was wondering about too - as all pressures are concentrated at that very top point of the overflow box connection -

 

[NewSchool04]

I built one in my tank, no problem. I would have done it external but I didn't trust my first silicone job to be something that could fall off the tank and drain my tank! Once I used the stuff I realized I could hold up a small building with it.

Here is some pics:

The overflow, I ordered the glass from a local shop, about 25 buckets for tinted and used black silicone.

On the tank and it really does works great, silent. I used two 1" drains just incase one got blocked.

 

[hansnfrans]

NewSchool04- Why didn't you leave the "overhang" on it so that you could allow some SPS or GSP to encrust it and cover up the overflow box?

 

[rickyb]

Go to Coral Paradise, Jimmy has the external overflows on all his tanks.

RickyB

 

[NewSchool04]

I really didn't like the idea of having corals floating above my rockwork. It didn't seem natural and more of a pain than it's worth. A pain as in trying to keep things on the shelf without falling off or overgrowing into the overflow.

 

[AuroraDave]

I've never heard of Calfo's version of the external overflow so I dont know what you need help with.

However, I have a 180 (same 72x24x24) that I installed an external overflow many years ago. The box is 14x14 and 5" deep.
My tank is 1/2" acrylic, but I think the overflow is only 1/4".

I cut a 13" long slot on the back acrylic pane with a regular saw and used a dremmel to sand it down. It is 2" high. The water exits the slot into my overflow, which has (2) 1-1/2" BH for the drains.

You are welcome to stop by or call with any questions.
Dave