Overflow Box Mystery

JimDog2015 · Nov 27, 2015

My overflow box has two U-Tubes that feed the sump. For some reason the tube on the left hand side looses its prime after a day or so. I have checked for leaks in the tube and even when I swap the tubes around, the left tube loses prime after a day or so.... I can't figure out what the issue is.

Has anyone else had this problem??

tgp4274 · Nov 27, 2015

to slow of flow?????

JimDog2015 · Nov 27, 2015

No the left tube gets an air bubble in it and it grows until the flow in the tube stops due to the prime being lost. The inner box and the outer box are both full to the water line. Just the left tube looses its prime, but the right tube maintains its flow with no issues. The flow to the sump is equal to the return to the tank (1200 gph) .... Its driving me nuts

tgp4274 · Nov 27, 2015

could try drilling a hole in the tops of the tubes and buy a lifter pump...... :/
not sure how a bubble would be getting in.....

Jp978 · Nov 27, 2015

Change the tube to a single 1" tube or up the supply flow

Robink · Nov 27, 2015

My tube used to do the same thing. Get an air bubble that would get bigger and then stop flowing. Don't know what caused it, but ever since I got a bigger sump I haven't had the problem. Same overflow box and tubing. I do clean the sponge at least once a week (same as before). Maybe a better flow into the sump??

pondman · Nov 28, 2015

Mine does the same thing I found that the water spilling over from tank to box made small bubbles over time making the tube collect them I put a piece of plastic next to tube to break up the bubbles works good

JimDog2015 · Dec 1, 2015

pondman said:
Mine does the same thing I found that the water spilling over from tank to box made small bubbles over time making the tube collect them I put a piece of plastic next to tube to break up the bubbles works good

Ok thanks, do you think you could take a picture of what you did? I'm having a hard time visualizing it.