Hose filters

[Chartreux]

When filling a spa/hot tub do you recommend using hose filter?
If so which one?
I found the following hose filters, Pure fill spa, prefresh and pure start.

and for the shell do you suggest Leisure time spa fast gloss?

and when do you take the first water sample in for testing?

Thank You

[rosewoodsteel]

I bought one on Amazon that worked great.   Not sure what brand.