Missed a step when filling my new hot tub

[pojv]

It appears that I missed a step two weeks ago when filling my new hottub, I neglected to add a  Metal Free stain/metal preventer. Is this something:
       That I can add now
        Will it changes my PH balance
        Is it better to wait two month drain and add then

Thank you
Phil

[Sam]

You can add it now and it won't create any issues.  What is your source water, city or well?  Does it leave evidence of high metals or minerals around faucets, etc?  If not, you really don't even need to add it.