How long can sump be with water movement

[jcs11236]

I don't know what time last night my pump decided to turn off causing my sump/back compartment of AIO to have no water movement. Woke at at 3:30 to find it all still. Tank had movement since mp was on. Turned sump pump back on. Will there be die off in the back? Should I be worried? All inhave back there is chaeto chemipure n sponge. I turned it and left to work. Now I'm a lil worried. Dosing pumps came on as well in the sump during the night. I'm assuming levels shot up once pump came on
Just rambling.

 

[KathyC]

It likely won't cause an issue, though it might be a good idea to change the chemi-pure and add a little more carbon in a media bag.
Unlike a canister filter that gets no oxygen at all when they are off - your back compartment is exposed to oxygen, so it isn't much different than turning off your pump when you are doing a water change. For all you know it may have shut off right before you woke up.

You mention you turned it back on? Any idea what caused it to shut off?