overflow

[newellio]

Looking for a little feedback about this design. i have a 40G hex acryllic hex tank. rather than put the overflow inside the tank i was thinking about using Weld-On on attaching it to the back of the tank and cutting a whole near the top for water to flow into it.

The box i planned on putting on is roughly 8in long by 3.5in deep with a 1in tube in the bottom leading to the refugiam in the bottom. Then i'd cut another small hole inthe top to have a pump push the water back up. i haven't really yet thought about what size pump to use.

I guess my real question is, does anyone forsee any issues welding a overflow hanging off the back of a tank?

[Bloodydecks]

Just make sure your aquarium is super clean where you make the bonds. Test the box for leaks before you drill the main tank. If it passes, then drill overflow, then seal it with tape, and test it for leaks again. This is to make sure the vibration from the drill didn't break the bond anywhere....if all passes, then drill the tank.

The only draw back I can see is you may have a gurgle / sucking sound issue. If you do, take a piece of PVC and drill a dozen small holes in , and put n the overflow box drain hole...trying to equal out the flow enough so that you don;t get the sucking sound....if you still have the noise, drill a few more holes, and repeat as needed......but only do a few holes at a time, until you find that perfect combo.

ALso..you may want to go 12 x 4 x 4 insted of 8.5 x 3 x ? and i think a 3/4" drain would be fine.

[ToddTT]

Have you considered overflow boxes like these? No drilling, and it gives you the option of relocating it if needed, or reusing on another setup in the future. Mind you, I have no experience with these myself:

MarineDepot.com link:
CPR Overflow Boxes

[newellio]

what would be the benefits of going with a bigger overflow box?

on a cool note i found out i can bend plexi-glass with just a heat gun. so i get to eliminate 2 of the seems where i could have a leak.

[newellio]

i did look into the siphon overflow, i haven't really ruled it out but i do have concerns. for instances what happens if for some reason the siphon stops. it would cause the refugiam to empty and the pump to run dry. or what happens if for some reason the power goes out and the siphon continues to flow until it reaches equilibrium, but then fails to start up again when power is restored and the pump starts pumping.

i'm probably over thinking it a bit.

[Bloodydecks]

what would be the benefits of going with a bigger overflow box?

on a cool note i found out i can bend plexi-glass with just a heat gun. so i get to eliminate 2 of the seems where i could have a leak.

you just want to make sure the box is big enough to allow for the flow rate...if its to small it may fill to quick, and the drain won't be able to keep up.....

If you use a one inch pipe like you planned, the smaller box probably won't matter (but I would rather go to large, then to small)...in my experience, 3/4 is much easier to work with, but in the big picture, and after thinking about it...one inch should be fine.....but i would still consider the larger size box.

good luck..post a report back on how it turned out.

[newellio]

you just want to make sure the box is big enough to allow for the flow rate...if its to small it may fill to quick, and the drain won't be able to keep up.....

If you use a one inch pipe like you planned, the smaller box probably won't matter (but I would rather go to large, then to small)...in my experience, 3/4 is much easier to work with, but in the big picture, and after thinking about it...one inch should be fine.....but i would still consider the larger size box.

good luck..post a report back on how it turned out.

ya i think i'm gonna stick with a 1in hole, and take your idea of the bigger box. this is my first time really building a tank, stand, lid basically the whole nine yards. whole bunch of trial and error and hopefully no living room floods when its finished.