Originally Posted by Brent

I read #2 all the time, but most setups I see use inside air simply because its easier since the inflation fan is on the inside. That's what I do. Most inflation fans are of the squirrel cage type (rotating vaned drum) and the air is introduced from a hole around the axle. Mine has a simple plate that can be slid to partly cover the hole to regulate the inflow. I don't bother measuring the pressure, but keep the opening wide enough to to just keep the plastic 'taut' so it doesn't flap. This is much simpler and less expensive than a rheostat or fan controller. Most inflation fans made for this job have this cover plate.

Brent
EvergreenGardenworks.com
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