I have a 4" well that I use to water my cattle, the well is only 60' deep with the pump set at 30' down the casing. I have water 5' below ground level. Currently I fill the tank daily but would like to install a pressure tank and pressure switch with a float valve on my troughs so I know they will always have fresh water. I have added a inline RV water hose filter off of the well pipe to try and remove some discoloration and sediment I see in the water and on the bottom of the water tanks.

With no filter attached I am getting 22gpm
With the filter attached I get 15gpm

Two questions,

Does the fact that I am restricting the pump some by adding the filter hurt it?

Should I use the filtered gpm rate or the non filtered gpm rate to size my pressure tank?

I imagine I would always keep some kind of filter on the line unless the water clears up over time.

Any help or advice would be greatly appreciated.