It's up to you. If it's a cheap filter replace it, if it's costly save it. Or depending on the model and type take the filter and get it out from inside before it breaks and then you can buy a new filter housing and use cheaper filters.
If it's a CC-10 type filter and only been used about a week or two I put it in the freezer till needed in a few months. Does not affect it at all. They are inexpensive but hey. If it has been used a few months I toss it.
I use an external filter and replace it every season as they are inexpensive. In between trips I store it in the home fridge. Maybe overkill but as an experiment fill a glass with water from your RV tap. Let it sit in the sink in between uses of the RV. The prior to next outing, look at the glass and decide if you are OK with the water. Especially in the summer, lots of things will grow in it.
2015 Freedom Express 248RBS
TV 2015 Silverado HD2500 Duramax
TST Tire Monitors
Honda 2000I + Companion
2 100W solar panels
2016 F350 6.7L LB CC Reese 28K 2014 Chaparral Lite 266sab
"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety." 2014 19 days camping 2015 17 days camping201620 days camping