The 1/4' nipple going to the water well pressure switch became clogged with grit,what would be the best way to prevent this in the future. Thank You

If it's just grit, or perhaps a sandy material, I'd make sure the small pipe went upwards to the switch rather than sideways. Bear in mind that water only stands in that pipe... it doesn't flow. So I would think that having the pipe go up would prevent material from just settling in the pipe. However, if it's a sludgy, rusty accumulation, then that might be a little harder to stop.

Hopefully someone else might have a better answer.

I neglected to sat that the nipple is vertical & that the grit is not sandy but rather coarse.