drained pool 2/3 through drain, 1/3 balance now only air ??

[raimondo]

Hello,

I STARTED DRAINING MY POOL THROUGH THE FLOOR DRAIN, THE POOL WAS QUITE FULL , NOW I HAVE ABOUT 18 TO 20 INCHES REMAING , ALL 0F A SUDDEN THE ONLY THING THE PUMP IS PULLING IS AIR, IT SOMETIMES TRICKLES.

THE VALVE TO THE SKIMMER IS SHUT OFF, I TRIED FILLING UP THE SKIMMER , AND THEN TURNING ON THE PUMP , I FILLED THE BASKET IN THE PUMP, IT PULLS FOR A VERY SHORT TIME AND THEN AGAIN ONLY AIR?

please help!

RAIMONDO[/b]