Preventative maintenance. Sometimes you have to "de-fur" the problem. We use a hand vac and a rubber brush (works especially good on the Sunbrella and the carpet in the cabin). The bilge pumps in the 25 are under the cockpit sole and the interior step; the interior one doesn't get used. I clean the bilge pump under the cockpit every so often. We've never had a problem with fur, but occasionally grass and grit get in there. The base is slotted and there is an internal screen; pop the pump out of the base and clean out the crud with your fingers.
Best wishes,
Jim B.