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The secondary pumps for our hot tub just emit big bubbles constantly, instead of working normally. The primary pumps work, but weakly. I’ve tried cleaning the key filters that I could find (including on the floor of the hot tub), filling up both of the filter bucket areas and the O-ring and the main pressurized tank with water until it just overflowed, and nothing seems to have any effect.

Any other tips for what might be causing the secondary pumps to not work at all and just blow bubbles, and for the primary pumps to be so weak (and how to fix it)?

Thanks!

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