yes there is.
via google, read up on Merv ratings for air filters. The merv rating will help you find out how small a partical you want to filter. After that read up on filter air flow restrictions. after that search for 4 to 5 inch thick air filters. I dont know what type of filter holder you have, so you will have to figure out what works.
good luck... but remember restrictive air filters can kill your indoor blower motor and maybe even make the compressor unhappy.
Probably gonna be better off using a MERV 13 media air filter, and then add a HEPA filter system. Most 5 ton units don't get enough air so as it is, let alone when trying to use anything higher then a MERV 13..