I stopped using the Walmart blue filters last year. They not only quickly limited water flow/pressure but they really did not filter out all I would like to see them filter. We even had to stop using that water for our dog (German Shepherd) as the water frequently gave our dog the runs, and we would see unsightly scum on floating on top of our tea/coffee. With advice from some fellow RVers, we switched to a double canister system where you can pick the filters you want to use ... or you could even go to the 3 canister filter. Here is what we got ...
https://www.rvwaterfilterstore.com/images/Cannister Dual.jpg .... and are the dual canister choices. SOOO easily to quick connect too ... no more runs from the dog no matter what campground water we use ... no more scum floating on top our our hot beverages.
https://www.rvwaterfilterstore.com/WCStandardCanisters.htm#popularsystem
One of my filters suggests change out ever 3 months .... the other every year.
Wife even started using sink water again to drink and says it definitely tastes better.