Internal Overflow

[firstone]

Hey Gang,
Hope all is well. I was wondering, Ive been doing research on sumps and overflows and what not and have come to the conclusion that its in my best interest to build a internal overflow, I am using an All-Glass aquarium 29 gallon and as far as I have seen its not tempered. So heres my question, how do i construct the actual overflow, i was planning on using a couple of acrylic pieces and making a corner then having the return and to sump coming out of the corner then just making slots for water to go through, finally silicone-ing it to the glass, but how high do i make it, the slots should be just a couple of inches below the water line i assume and then what prevents the water from the return line to not just be re-filtered and how do the fish not get into the overflow part, in my head i just see the water going from the return right back into the overflow and not getting any of the bottom of the tank water wondering if anybody has done this and has any suggestions or if anybody has pictures thanks a million and sorry for the mammoth post.

and not to be greedy but what size bulkheads do you all recommend, i have no equipment as i will buy once i know what size the bulkhead will be...

whew, that was long sorry :)

[SaltTinker]

I'm sorry to inform you, but your AGA 29 gallon aquarium is probably tempered. The glass isn't real thick right? Then it's tempered.

Drilling into tempered glass can be unsuccessful if you do it yourself.

I've seen diamond studded hole saws that might work in your situation, but doesn't have 100% success. If you find a place to do it, they will not pay for a broken tank if it doesn't work.

I've seen someone use a sandblaster to make a hole in a 55 AGA, but the hole wasn't perfectly round.

If you do get it done, you could leave out the acrylic box, have a short tube connected to the bulhhead, an elbow, and another tubing going up to the where you want the water line. Some LFS do it this way.

As to the size of the hole, it needs to be 1/4 larger than the size of the bulkhead to account for the threads. Say 1 1/4 for a 1 inch bulkhead, but really depends on the size of the return pump and the size of the tubing you want to use.

Good luck.

SaltTinker