New hub and old hub. Too bad they don't attach the same, but the parts are damn similar for a Pac-Fab Triton from the 80's, versus a current Pentair Triton II.
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Here's what a groove created by sand looks like. This must be the culprit to where sand was blowing back in, though the entire web of lateral spokes were cracked long before I got into the filter yesterday. The spots where it cracked show some aging and wear, as if they'd been there for a while.
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