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Or any of several keen commercial solutions.
That's neat. I'd stay away from any small screen type filter, though (like the heater hose filters shown). I've made my own filters out of stainless steel screen. The area is not large, so they tend to get clogged up quickly and hinder cooling. One advantage to the stocking technique is that the debris gets contained in a lump at the toe end which just floats around in the upper tank and does not hinder flow in any appreciable way. Of course, the see through filters have a great advantage, but do you really want to show off how much crud you've got circulating around in you cooling system? 
D/W