I would follow Ben's directions. In fact, in this newsletter he talks about shocking with cal hypo in the skimmer
http://www.poolforum.com/pf2/showthread.php?t=10246
and he gives much fuller directiosn here:
http://www.poolforum.com/pf2/showthread.php?t=10217
He suggests that by using cal hypo this way excess calcium precipitates out in the filter and acts as a 'filter aid'. Worth trying but do keep tabs on your
CH and if it climbs beyond reasonable levels switch back to bleach.
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