sump help

[emonemo420]

alright so i have had my sump up and running for a while and i still dont trust the fricken thing...mainly because everytime the pump is shut off (by my doing) and i then turn it back on after w/e im doing the overflow never starts back up.....
however when i did my water change last week and i turned the pump back on, the overflow worked normally...
so my ? is does it matter how much water is drained out of the tank and then filled back up for the overflow to start working again..now mind u i havent tested it lately by killing the pump, letting it drain, and then turning it back on but every other time it hasnt worked

to make it clear.....when my pump turns off i have it set up so only 2-3 maybe gallons drain into my sump...which on my 55 isnt a whole lot... but when i changed the water i took alot out.... so maybe if i made it so more water is backdrained then i wont have an issue?? any of this make sense or is any of it true?

 

[a1amap]

Loss of suction. Take a Pic. I know you are going over the top but what kind of overflow?

 

[kaptken]

the over flow should restart as long as you do not lose the U-tube fill. if you expose either end to the air when the pumps go off, it breaks the syphon and it wont overflow when the pump starts again. so both ends of the U-tube need to stay submerged in a pool of water when the flow stops,......

OR ELSE.!!

You might be doing the wet foot two-step when you get up in the middle of the night after a power falure restart.