Flushing/Surging of water into sump

[smoothie7]

I am having an issue with water coming from the overflow to the sump. It goes in surges. Sounds like a flushing. Doesn't matter if I use sponges, durso standpipe or nothing at all. It still does this. Please watch the videos. All input is greatly appreciated!! Thanks.

View My Video

 

[smoothie7]

Here is a close up of the sump
View My Video

 

[smoothie7]

Here is a picture of the overflow near the bulkhead. The water level always stays at this level. It never fluctuates even when you hear the flushing though the hose into the sump

 

[smoothie7]

so heres the update, we built a complete 1" durso standpipe and currently a 9/64" hole in the cap and our water level is maintaining above the elbow and we are still getting some gurgling not so much flushing like it did have. is it possible that the pump that I have quietone 4000 (950gph) is pumping too much water in and the overflow can't send it out fast enough?? Thoughts?

 

[Dmann]

dino

 

[Dmann]

I made a reverse durso for my overflow to quiet it down. Worked really well

I was getting the same thing. Flushing ang gurgling. Made the reverse durso under the tank. Make sure there is a nice hole in the cap. and the elbow is halfway submerged in the sump

dino

 

[54seaweed]

I was getting that same flushing sound the guy a pet store suggested adding a little more water to main tank and sump ,
low and behold it went away almost instantly

this is my wet dry sump

also note I don't leave a water gap between the top band

 

[Ingy]

I tried to view the video, but it says I need to create an account first. That ain't gonna happen.
So, it looks like an integral overflow on the back of the tank. And there's no standpipe in the overflow regulating the tank level that I can see. What happens if your return pump shuts off?

 

[smoothie7]

currently with the durso standpipe in, if we lose power, the water in the overflow is going to fall just under the elbow of the durso and it will suck in through the discharge nozzle until its just below it. This water goes back into the sump at that point until power resumes