Prefilter 6473-364 SpaGuardTRIO then this is likely the

then this is likely the culprit

J-300 Series Flow Switch 6560-852

Turn on filtration system

Repeated applications increase water repellency

This was used on hot tubs with the LCD control system only

Prefilter 6473-364 SpaGuardTRIO then this is likely theJacuzzi Pre Filter Fill your spa with the most pristine water possible. Use one of these with on each fill up. The Microfiber Disposable PreFilter takes out calcium, rust, sediments, and other undesirable elements from your water before you fill your spa. Good for up to 3 fills, the MicroFiber Filter meets FDA and NSF standards. Attaches to a garden hose and great for people using well water.