Pumping water from the sump

[Terry chancellor]

I recently had an engineer to build a septic tank in France. He also ripped up the pipes for the pool. I had the pipes repaired and the vacuum and sump worked ok, but with some air showing. I drained the pool for the winter so it is now half full. I then discovered another tiny leak. I now need to pull water from the sump to test every thing, but it only pulls air. Can this be done or is the water level too low.