Hey there, you could certainly do that but I don't quite understand why you want to prevent the very thing a Skippy is designed to do by keeping it off the bottom. If your pump is not picking up or preventing the sludge it may be too small or located poorly or you might need to add a pre-filter.

If the "malfunction" you are concerned about is that the water will be pumped out of the pond for some reason (broken hose, spillway plugged, etc) rather than returning to the pond, and the pond left high and dry I came up with a solution that works for me.

I got a sump pump low water shut-off gizmo at a place like Lowe's or Home Depot for about $20. The pump plugs into it and if the water gets too low, the electricity to the pump is turned off.

After having the pond empty twice in two weeks, leaving fish flopping around in about 2" of water, I decided the $20 was worth it!!

Circulation is always good, can't go wrong there. That said, my pump/skippy intake is elevated on a cement block so there's a few inches of water left in the event of a malfunction/clog. Not perfect but buys enough time for me to get home from work & rescue my babies if something happens while I'm away.

If the low water shutoff gizmo provides peace of mind, it's money well spent:) As for me, my system works fine & my $ is still in my wallet. (I wouldn't hesistate to open that wallet, however, if I hadn't found an alternative - thanks to the experienced ponders here).

Ya gotta do what ya gotta do...do what works for you.

blessings,
~digger

Peace of mind for backup protection is value to me - I had some leaves clog the spill of my little pond(make shift skippy) and overnight it pumped itself down to a few inches.
Maybe I've been working in Redundant backup power system too long, but I keep a spare pump and repair parts on-hand. And in the last 10 years, they've been "fish savers" on several occassions.