External Overflow with Durso pipe

[jharding08]

I just recently redid my overflow plumbing. I currently have a CPR CS100 External Siphon overflow with a 1" bulkhead. Before, I had a 1.5" drain on the outside of the bulkhead (thought I could screw into the thread on outside of the bulk head. Don't ask, I was a newbie). The durso pump had a air vent hole a bit smaller than 1/4" where i could put a piece of 1/4" airline tubing to silence it. The outlet of the 1.5" plumbing went into a filter sock, which meant the pipe was under water. The only problem with the plumbing was that it would leak when the water backed up after the bulkhead where the plumbing screwed into the bulkhead outside. I put some putty on it to try to seal it, but it wasnt a good solution.

Last weekend I tore out the 1.5" plumbing and put in 1" plumbing with unions. The 1" pipe is inserted into the inside slip side of the bulkhead and glued with PVC glue. The plumbing runs down about 2 feet, through a hole in the stand and then runs 3 feet to the sump where it drops into the water and filter sock (end is under water).

I am seeing a couple things with the new setup:
1.) There is a small leak in the joint between the bulkhead and the pvc. It isnt the bulkhead seal that is leaking it is the coming between the bulkhead and pvc. And by small, I mean 1 drop every 5 min. I know that salt creep could possibly seal this, but if not, how would I seal it without having to replace the bulkhead/pvc/union, etc?

2.) With the 1" pipe and the filter sock and the pipe exit under water, i am getting alot of bubbling in the sump and the level in the overflow is going up and down. I drilled a bigger hole in the durso about 1/4" and that seemed to help, but what is the logic behind a durso pump and the overflow exit? Should it be under water, thus creating a siphon? or above. If its in a filter sock, it could be out of the water, but when the filter sock traps detritus, it will make the pipe theoretically under water.

3.)I am looking to upgrade my sump in the future to a model where the overflow exits are in their own chamber and the water then flows up and over into a filter sock chamber, then down through into skimmer chamber, then baffles, then refugium, then return chamber. Something like this:



I am looking to build something 36"x20"x16", does any one have a complete dimension drawing of this with 3/8 or 1/4" acrylic? I want to make sure I get the filter sock holes correct and deep enough.

[jharding08]

I didnt mean to put the question about the sump dimensions here. Just questions about the overflow plumbing.