Suction Side Problems: Air Leaks, Bubbles in Returns, Pump Won't Prime, etc.

[PoolDoc]

I can't think of a series of causes and effects that would result from your change of sand, and lead to a suction leak.

Oops. I thought of something.

It *is* possible that your new sand has lowered back pressure (really, resistance to flow) on the output (effluent) side of the pump. This would in turn lead to higher overall flow, and thus increased negative pressure on the input (influent, suction) side of the pump. That might, in turn, stress a pre-existing weak point in your suction lines or valving, and possibly increase the damage or opening there.

But, it still comes down to there being a leak in the suction side piping and valving. The sand might have triggered a worsening of the leak, but it didn't cause the leak in the first place, and is not related to the location of the leak.

[Watermom]

By the way, you do not need nor want to backwash every two days or even every time you vacuum. You only backwash when the pressure rises 8-10psi over clean filter pressure.