Overflow advice
 

Hey fellow reefers

Need some input to help my buddy out with his 90 Gallon cube tank.
It's drilled in the center and he is building an overflow there , to ensure the ABS 8" pipe adhere's to the glass what is his best way of doing so ?

Thanks

Best way would be not to use plastic and build the overflow from glass like you're suppose to. If that's not an option all you can really do is silicone it and hope for the best, but I wouldn't recomend it.

Agreed, 3 pieces of glass will only run you about 30-40 bucks (depending on size and supplier) and will save you a bunch of problems. Remember to leave about an 1/8 inch between panes for silicone. dont want glass on glass.

Silicone doesn't stick to ABS very well. But if you scuff the mating surface with sandpaper, it will increase the "tooth" and the silicones grip. I am asuming he wants a nice round looking overflow in the middle of his tank? It is easy to build a box on the back wall out of glass too though. Silicone really sticks to glass well. Any glass shop will cut the pieces needed and they won't cost much at all.

big flood when the weak bond to the ABS lets go, use glass.

Ive siliconed ABS overflows in and no issues. on 22" water heights too. Heck, look at alot of corner Overflow tanks. Whats the overflow made of? ABS, and siliconed to the glass......


Also, only flood issue would possibly be on a power outage IF the silicone let go. But let me tell you, where I live, I get 10-12 outages a year, some for hrs at a time. Never one did my tank have an issue. If you have a standpipe style drain in the overflow you won't drain the whole tank anyways..

I've siliconed a piece of acrylic to the corner of my sump to hold my ATO but know I could easily pull it out by hand. If it was glass to glass be looking at a fight with razor blades. Also in the corner you have the support of the sides and bottom edges, this was described as sitting in the middle if the tank. Not saying it wouldn't work but there's better ways to do things.

What size bulkhead has he drilled for? does he have a sump return bulkhead near by also?

There are lots of ways to do this better and not what we are suppose to do, that's the easy way out, why don't we think about what we need to do and then figure it out, using and taking up space with a glass box in the middle of the tank is both wasteful and expensive, re-think the problem, make your mind work and come up with a better solution, and save money.

And who says were SUPPOSED to use a certain product anyways? Where would we be if no one broke from convention? Just because Joey and Billy use it, does it mean you have to too?