Sump issue

[oscarman2003]

ok i have finished building my sump over flows out of pvc i at first i was running 1 3/4in overflow. i am running a 650gph pump. the tank 125 sump is 55g. one sump was not enough so i built a second one and everthing was working fine. the issue is that i simulated a power outage everything was cool till i turned power on. only one overflow restarted and i can not figure out why any suggestions i will post pics

 

[oscarman2003]

Pics


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[cjbarth]

are both intake tubes exactly the same length? (where water goes in)

 

[houie925]

If I remember correctly these restarted more reliably for me when there was a longer pipe between the bottom bend and the output. It looks like your output is near the bottom bend. It's been a few years since I've used one of these overflows though. It may also be a small air leak at one of your joints or valves. Doesn't take much air to stop one of these overflows from restarting.