We had Nova system for 6 years at single family house and had Nova installed when we bought our villa close to 2 years ago. I have always changed my own filters after the initial Nova install. I highly recommend NOVA. I also use the filter in my refrigerator, but I think it is probably overkill. Once the filters are installed or replaced you need to run several gallons of water through the system prior to drinking. Ok for anything else.
3 filters for Nova Water Filtration System on Amazon.com:
1st Stage : Sediment Filter (5Micron), 2nd Stage GAC Block (Granular Activated Carbon), 3rd Stage Carbon Block (5Micron):
Amazon.com
Currently $79.50 for all 3 (a package deal).
Tool to remove canister:
https://www.amazon.com/Pentek-Plasti...TE0WWASQKMA50R
O rings for canisters:
https://www.amazon.com/Captain-Ring-...TE0WWASQKMA50R
Silcon Grease:
https://www.amazon.com/Waterproof-Si...VYZ7PN1VVX9KYS