Overflow options

[Navyblue]

I am considering replacing my 120G. It is currently on a siphon box. I am thinking of doing a drilled custom tank.

My cabinet has no hole underneath, meaning it would be easier if I have the hole at the back, but my LFS doesn't recommend it (they say it is prone to leak). Personally I imagine the bulkhead might stress the tank if it is not done properly.

My questions is:

- Where should the outlet hole be located?
- How large should the overflow box be?

What would happen if I do without an overflow box and just have a pipe that sticks upwards to let water flows in? Gargling noise? If would work, it seems that the easiest way is to have the hole drilled like 4" under the rim at the back of the tank and have an elbow on the bulk head that faces up. What am I missing?

[RVANANO]

One of my LFS's said the same. The funny thing to me is that they all can leak. And which would you prefer if you have to replace a fitting, draining the whole tank or just 10%?

I just had my 120 drilled at the top for overflow and returns. I had a tiny leak and fixed it with a strap wrench.

IMO, the LFS's who say that just don't want to deal with the drilling and the potential for breakage. Plus they probably make more on standard tanks.

[Navyblue]

Do you have a photo on how yours is done?

Thanks.

[Navyblue]

Ok, I saw your pictures.

Anyone else?