Moments before spontaneously combusting lurker was heard to ask:

im not so much worried about too much current as much as my filter not
being able to handle it. seems to do ok with the 750 but was designed
for a 550! i pretty much made up my mind on going with the mag pump
though.

about prefiltering, your ideas sound like they would work good.
could i cut out a peice of normal filter material that holds bacteria
in external filters and just place it over the pumps intake? or would
covering the entire pump be necessary.
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Don't just cover the intake itself or the filtering material can clog and
slow or stop the water flow. I wrap the entire pump in the window screen -
at least 2 or 3 layers. I don't depend on my pumps being biological
filters. If the screen is stiff and don't want to stay in place I put some
stones over it to keep down.
--

Koi-Lo.... frugal ponding since 1995...
Aquariums since 1952
My Pond & Aquarium Pages:
http://tinyurl.com/9do58
Note: There are two Koi-Lo's on the Aquaria groups.
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