dirty glass portlights

[RockysMate]

It kinda looks like running paint, maybe gelcoat on the outside.  I tried glass cleaner, vinegar, no luck.

[dutchie]

The portlights are made of hardened glass. If you can some where buy these old Gilette razor blades, The old fashion single blades, you can try to scrape it off. Don't try this on the escape hadhes

[barrylab]

I have a white haze on the lower half of my port lights that doesn't respond to scraping with a razor. I'm assuming it's calcium scale, and intend to soak the glass in PBW (professional brewers wash) or B-Brite (another brewers wash) that's used to remove scale from brewing equipment. PBW has worked wonders on glass carboys I use to ferment my own beer, so we'll see how it works on the port lights. Relentless is shrink wrapped for the winter, so I can remove the glass to do this. I'm taking the glass out to replace the seals, so it's very little extra work to soak the glass in PBW.

PBW is safe for stainless steel, and B-Brite may be ( I've never tried it). They are both caustics that break down organic materials.
I get both PBW and B-Brite online from home brew supply stores.

OxyClean would be another choice, but again, they need to be removed so that you don't damage the seals around the glass.

I'll take before and after shots to add to the forum.

[Dale Tanski]

I am willing to bet it is the plastic film between the 2 layers of glass that is failing.  Your fixed ports are laminated safety glass.  When that stuff gets old or water gets to the edge it fogs.  Makes sense that it is on the lower portion of the glass as that is where the water would collect as the gasket fails.  I do not think anything will fix it.

Dale