Here you can see the results, a perfect hole that fits the bulkhead snugly. I used the drill on a low speed to make sure the acrylic did not melt while drilling.
And here it is with the bulkhead in place...Just to show it fits.
Well, I drilled the two bulkhead holes without difficulty. The second bulkhead is the return for the refugium. Even though I plan on having low flow through the refugium, I went ahead and used a 1 1/2" bulkhead to make sure there were no problems with the drainage. I positioned the refugium return at the front of the sump, and about 6" below the top. In the refugium the overflow is 2" below the top. Both the sump and refugium are 16" tall, so this gives a 4" vertical drop from the refugium to the sump allowing good gravity drainage.
After the bulkheads were drilled, I attached the 4th vertical wall in the same manner. Please note that in the picture, the sump is inverted. The "bottom" is actually at the top in this picture.
I am sorry I neglected to photograph the addition of the bottom to the sump. However, it was simply a matter of doing one "end" by clamping that portion with the clamps, gluing the seam, waiting...then moving the clamps to the opposite "end". After this, I applied both clamps to one side..and glued that seam, then the other side. It is importan to note that I made sure that each seam I was gluing was positioned "down" at the time of cementing...this allowed gravity to help with getting the cement to flow easily into the seam. The gravity was not so much a help with the capillary action as it was with keeping the cement from dripping in places it wasn't meant to go.
After the cement was set...I removed all the paper EXCEPT the very bottom sheet. Here is my baby with the bulkheads installed:
