ekovalsky
New member
I'm planning a custom glass tank that will measure 76x28x28. The rear and sides will be standard glass, only the front panel will be viewable and will be starphire.
For several reasons I'd prefer to incorporate an external overflow hanging off the rear panel on the right side, rather than have the more common internal overflow. The external overflow would maximize real estate in the tank, improve accessibility for rmaintenance in my setup, and also simplifying plumbing. Tank is destined for an in-wall (niche) placement; the external overflow would protrude through an opening I will make in the back wall of the niche into an equipment closet behind it. Unfortunately the maximum width of this overflow, even if it is extended all the way to the edge of the rear pane, is only about 14" because the closet is shallow and oriented perpendicular to the tank, and there is some structural house framing behind the rest of the rear panel that I cannot remove.
Actual tank volume, based on internal dimensions, will be 224-240G depending on glass thickness. I'd like to get at least 3x tank volume as sump turnover, i.e. 750-800GPH, which will gravity feed a recirculating skimmer. Based on the overflow calculator on RC, 12" is the minimum acceptable width which I will barely get, but I assume this value from the calculator is for a standard overflow using teeth ? Rather than have the teeth, I would instead design a weir by reducing the height of the rear pane in front of the external overflow box. My hope is that, without the teeth, I will get the same surface skimming as a longer standard overflow.
The weir should be easy to incorporate since this tank will be built to spec. I do not want crossbraces, nor do I need a braceless setup since there will be a canopy over the tank. So my plan was to have eurobracing around the entire top. The gap between the eurobrace and the lowered top of the rear pane at the overflow would be small enough to keep fish and most other aquarium inhabitants from entering the overflow.
But... the eurobrace would not be in direct contact with the overflow section of the rear pane, because of its reduced height. Thus I am a bit concerned about stability of this portion of the rear pane and potential for bowing. Thinking about the design and function of a brace, it would seem that the bottom of the external overflow box, once secured in place with silicon, would act effectively as a brace itself. Is my thinking flawed ? As an added safety measure, I could also increase the thickness of the rear pane (build it as if it were to be braceless). I could also have it tempered.
Rest of the tank is fairly straightforward. Tempered 1/2" glass should suffice for the sides. The bottom will be either 3/4" glass or 1" SCH80 PVC with holes drilled for CL. For the front, I probably will overbuild and use 3/4" starphire though it isn't cheap. Not sure if it is worth using starphire for the eurobracing, I probably will if it isn't too much extra.
Any insights/suggestions/advice about the overflow setup or tank construction would be appreciated. I will try to post some diagrams since words only can be hard to follow.
For several reasons I'd prefer to incorporate an external overflow hanging off the rear panel on the right side, rather than have the more common internal overflow. The external overflow would maximize real estate in the tank, improve accessibility for rmaintenance in my setup, and also simplifying plumbing. Tank is destined for an in-wall (niche) placement; the external overflow would protrude through an opening I will make in the back wall of the niche into an equipment closet behind it. Unfortunately the maximum width of this overflow, even if it is extended all the way to the edge of the rear pane, is only about 14" because the closet is shallow and oriented perpendicular to the tank, and there is some structural house framing behind the rest of the rear panel that I cannot remove.
Actual tank volume, based on internal dimensions, will be 224-240G depending on glass thickness. I'd like to get at least 3x tank volume as sump turnover, i.e. 750-800GPH, which will gravity feed a recirculating skimmer. Based on the overflow calculator on RC, 12" is the minimum acceptable width which I will barely get, but I assume this value from the calculator is for a standard overflow using teeth ? Rather than have the teeth, I would instead design a weir by reducing the height of the rear pane in front of the external overflow box. My hope is that, without the teeth, I will get the same surface skimming as a longer standard overflow.
The weir should be easy to incorporate since this tank will be built to spec. I do not want crossbraces, nor do I need a braceless setup since there will be a canopy over the tank. So my plan was to have eurobracing around the entire top. The gap between the eurobrace and the lowered top of the rear pane at the overflow would be small enough to keep fish and most other aquarium inhabitants from entering the overflow.
But... the eurobrace would not be in direct contact with the overflow section of the rear pane, because of its reduced height. Thus I am a bit concerned about stability of this portion of the rear pane and potential for bowing. Thinking about the design and function of a brace, it would seem that the bottom of the external overflow box, once secured in place with silicon, would act effectively as a brace itself. Is my thinking flawed ? As an added safety measure, I could also increase the thickness of the rear pane (build it as if it were to be braceless). I could also have it tempered.
Rest of the tank is fairly straightforward. Tempered 1/2" glass should suffice for the sides. The bottom will be either 3/4" glass or 1" SCH80 PVC with holes drilled for CL. For the front, I probably will overbuild and use 3/4" starphire though it isn't cheap. Not sure if it is worth using starphire for the eurobracing, I probably will if it isn't too much extra.
Any insights/suggestions/advice about the overflow setup or tank construction would be appreciated. I will try to post some diagrams since words only can be hard to follow.
Your setup sounds really thought out. Seems like you really spent some time designing it
