How To Clean This Calcification from Glass

[Tygris88]

I am sure someone has posted it somewhere on this forum but I have done a quick search and read a few threads so thought I would post instead.

I purchased a used tank and there is some saltwater residue, calcification or haze or something that I cannot remove.
I have used the following techniques with absolutely no success:

I have used a razor to scrape off what I can;
Vinegar on papertowel overnight on glass then used a brush;
Citric acid on a paper towel and hung on the glass, waited 24 hours and then used a brush to wipe off.

I feel as though it is embedded inside the glass.

Does anyone know what to do here?

 

[TangerineSpeedo]

easy peasy... citric acid. One of two ways. Spray bottle and a razor blade or fill up the tank and dump a container of citric acid and a power head wait a day or two depending on the concentration drain wipe down with RODI

 

[bruno3047]

Lime-A-Way will get that tank sparkling new. Get it at Lowe’s or Walmart.