Spotty hazy glass

[ReefJCB]

My low iron aquarium is coming up on 8 years.

I’ve been noticing the glass getting hazy over the last year or so but it is in really weird spots.

Basically anything that was covered at one point with a suction cup, sand, magnets, etc does not have the same haziness. Even if it hasn’t had that spot covered in a long time, or even if it was temporary.

After doing some research I’m thinking maybe alkali glass corrosion. What had me 2nd guessing is this drip section that is new. I don’t know what caused it and haven’t been able to recreate.

I’ve tried razor blade, vinegar, alcohol, magic eraser.

Open to any suggestions or info

 

[Waters]

I had the same thing happen on my 10 year old, now planted freshwater tank. Haze becomes much less apparant when it gets wet.....when dry looks just like yours. I tried everything (even glass polishing with cerium oxide).....nothing works. I was told that it is a chemical reaction within the glass.