How do fix this?

looks like calcification. Try using toothpaste (the green kind) and rub it in. This is commonly used on headlights that have the same issue. I think it comes from hard water or something. Just put a dab of toothpaste and rub it in in circles. When done use some water and vinegar or rubbing alcohol to clean.

wet sanding? idk

>>1151377

It's almost certainly little other than hard water deposits.

Anything made to remove that kind of thing (usually the kind of thing meant for showers and sinks) would work. Vinegar would, too, but you could be rubbing it on for a while, depending on how thick it is.

Try a heavy duty toilet bowl cleaner.

CLR cleaner

File: IMG_2180.jpg (32KB, 600x600px) Image search: [Google]

32KB, 600x600px

>>1151497
+1
It's just hard water deposits dude. Hit it with a little CLR and watch it get crystal clear.

>>1151506
>>1151497
>>1151466
neat

>>1151377
I watched a video a while back comparing various cleaners for this task, and barkeeper's friend won out.

CLR is good, or if you have baking soda and vinegar mixing those into a paste will work also

If you can reach it by hand, use a clay bar. They're meant to pick up all impurities off of any surface. If that can't get that window clean, the window with never come clean

>>1151377
Just rub it with some muriatic acid or vinegar.