This is what many professionals use.
For "Severe BUT safe Cleaning"
Routine Cleaning and Protectant:
Also if you have mildewed vinly this will help you I am sure as it did me!:
Any chorine product or abrasive will etch the "vinyl skin" which is a surface UV protectent layer and will age the vinyl considerably over time and cause coloration and/or fading and micro-cracking.