replying to Danny D., Shay wrote:
Just for info. If you touch a main drain or swim around it, you wont feel
the water flowing nor suction. Reason being is because the covers are
anti-vortex. But aside from that, main drains are not like a bathtub where it
sucks in water forcefully. They pull in particals from the water, not just
water. And if you have a hot tub/Spa, you might see leaves or other debris in
the spa getting sucked toward the drains. This is because the drains In a spa
are stronger and the jets in the spa circulate the debris. And a main drain
isnt actually a drain, its a housing pipe, suction outlet that goes back
to the pump. Just wanted to put that out there.

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