Hi … I have an in ground pool with spa in ground next to pool slightly elevated above pool. When operating pool filter normally water flows over spa edge and waterfalls into pool.

I noticed this morning after the normal pump shutdown the night before that the water level in the spa was significantly lower (20" lower than normal) and the pool water level was higher than normal. It appears the water simply left the spa and went to the pool. I also noticed that the pressure in the system at the filter was at 10 psi (normally operates at 5 psi) so I cleaned the filter and DE grids and reassembled then fired it up again and noticed very little water flow at skimmer or pool sweep. Does not appear to be any visible air leaks and the pump motor primes sufficiently with no air bubbles.

Any ideas of suggestions would be greatly appreciated.