Setup question
 

I picked up a new nylon string acoustic. The action is alittle high at the 12th fret.

This might be a dumb question, do you set the nylon up about the same as a steel string ? Approx 5/32 at the low E and approx 3/32 at the high E ?

Will be using standard tension strings.

Thanks in advance
Bill

No.

Nylon string guitars require much higher action.

Flamenco guitarists are near 2.0 to 2.5mm, similar to a steel string acoustic. But classical players use 3.0 and 4.0 mm (high e, low e) up to 3.5mm 4.5mm. Standard "crossover" players will moreso enjoy an action about 2.75mm and 3.25mm or so.

You will LIKELY have a nut that is cut way to high. Get the nut slots checked before messing with the saddle. Once that is done, you can lower your saddle to your preference.