Thanks all. Yep, agree with Waterbear! I now resolve to tear down and clean every 3 months !

Another question, the cloth on the fins was rough, almost crunchy, felt a little like rough grit sand paper when sliding the fins down beside each other. Manual said that may get "Liming" on fins where get some scale buildup (initially filled pool with hard tap water, just this week gettig a water softener installed). So I think that is the problem. Manual said if "Liming" to bath fins in mild HCl soln. They are tall so I was thinking of doing this next tear down in a clean tall plastic garbage can.

Agree?