Ballast draining frustration

[LindMark]

I can't figure out when my ballast is empty. I empty and let set and gauge shows water. I empty again and again gauge shows water. Is there a way to make this easier? I have factory ballast on a 2012 210SANTE plus sacks in both back lockers and additional sack in walkway. I think they are empty and get the boat in garage and water keeps draining out the intake ports on the bottom of the boat. Why won't left over water just stay in ballast tanks? I can drain multiple cycles but can I hurt impellers or pumps if continue to run when they are empty? Any help would be appreciated.

[ScooterMcgavin]

I would suggest to pull the ballast impellers and inspect them. Do you know the last time they were changed? When they aren't worn out they make a very distinctive sound when it's empty. Worn impellers can also result in loss of water thru hull intake ports when pumps aren't on.
Nautiqueparts, your dealer, Amazon, wakemakers all have them. Your boat has the green impellers.

[LindMark]

Thanks. I will look into the impellers. After the factory tanks are drained empty, how long does it take for sacks to empty back into factory tanks? Still don't see how water could drain out when the pumps are the highest part of the system.