Guardian Filtration - Spa Filter Replacement for Pleatco PBF40 Bull Frog Spas,Wellspring 30 Coreless 10-00282 | Bulk Savings Packs (1, 30 Sq. Feet)

Filter 10-00282 has a slit in top and bottom cartridge that slips onto vertical in filter cavity. item in pic does not have that. bf a series. issue?

10-00282 has slits top and bottom to align on vertical in filter cavity. the pic product does not. Issue ?

Without the full length slit this will not work on b.f.x-series. seller hasn't responded to that question? amazon needs to take action for false info.

How often should these filters be cleaned-2 weeks, monthly etc.?