waynard wrote:
Hi,
this is a bit of an unusual problem. I recently bought a boat and it
came with a sonar unit that has a weird kind of mottling or splotchy
film of some kind on the screen. Almost looks like dried seawater
stains. It looks like you could almost scratch it off with something,
but of course, you risk damaging the plastic screen.
Any ideas what it is or how to remove it safely?

thanks.

My guess is dried seawater stains, and I would contact the mfg'er if
water and a micro cloth will not clean it. If it is a LCD flat screen,
they can actually absorb cleaning chemicals and destroy the screen. I
only use water and a micro cloth to clean all of my LCD screens.

If it is glass CRT screen, you can try any of the commercial glass
cleaning products, but i would make sure it was made to clean glass, too
many other cleaning products can have mild abrasives than can scratch
the glass.