The small 10 in blue filter for cannister at CW has good specs but 39.00 is high especially if you may have to toss it in a few days, such as RV Parks with wells in the Midwest another whole house or 10 inch filter for a prefilter with cheaper ordinary media helps that problem but buy several for replacements.
Since I had to re do our computer I lost links to store on line with the best filters. The ten inch whole house canister is about as large as practical in our coaches. Cartridges speced to get metals,poisons and nasties re not cheap but in the large whole houe size will perhaps last a season, especially if a prefilter for sediments is used. Sediments, Chlorine, Sulfur, iron and other metals and poisons with sediment fouling filters before the carbon block etc have a chance to load up, exception being sulfur and iron. So in order sediment,sulfur and iron get our filters early, then chlorine can get the carbon block, and then the metals and nasties.
Reminds me I have to order some cartridges before we head out.