"Retainer Brite" is an excellent product for cleaning invisalign aligners.
it cost about $40 for a year supply. (one per day)
its well worth the money.
on my first set, I brushed my aligners every single time I took them out and even used toothpaste sometimes. But even with all my efforts, towards the end of the 2 week cycle, the aligners started to smell and taste a little moldy.
thats when I decided to get "Retainer Brite". I use it in the morning to clean the aligners and when you rinse them off after using it, I brush them as well. This cleans the aligners good enough, that the rest of the day I only just rinse them off and don't brush them. In doing so, they stay plague free, scent free, and have a minty fresh taste in the morning. its well worth the expense.
Retainer Cleaner: Retainer Brite from Smileshop.com