Scratches in Aquarium Glass

Hi all:

My 110 gallon tank has developed some rather visible scratches on the inside of the tank. This is no doubt self induced from use of a magnetic scraper combined with rather hard natural gravel/sand/stones.

Do I need worry about these scratches weakening the glass? Is there anything I can do to remove/polish/diminish the scratches?

Thanks

Dean

Scratches that aren't deep don't noticably decrease the structural strength of the glass. Deep scratches, however, that bite through a signifiant fraction of the glass, are the technique that people use to score glass before snapping it along the line of the score. Your scratches are probably the first kind and have no impact on the strength of the glass.

Yes, there are things you can do to mitigate the appearance of the scratch. This article describes using cerium oxide to buff the scratches out: http://www.fitchfamily.com/glass.html
Or there are professional products designed and sold as kits: http://www.glassrenu...roducts.htm#pro
But honestly glass is cheap and used tanks abound on craigslist. Before you tackle the scratches in your glass you might want to also compare the cost of getting a new tank.

Can you get a picture of the scratches and put something next to the scratches for size comparison? Chances are, if it's from the magnetic scraper, it's just a cosmetic issue. As the other comment said, it would be cheaper and easier to either just replace the glass (assuming it's a deep scratch), or buying a used tank. Luckily, you live in an area where craigslist offers decent opportunities for replacement tanks.

I have never heard of a tank exploding due to scratches. Normally they leak from the seams. If you don't like the appearance the scratches can be buffed out.

Even scratches as deep as those used to cut glass, when short with random directions, will not effectively reduce the strength of the glass. Glass cutting depends on a continuous propagation to control the break location. This crack propagation effect is not dependent on any significant reduction of glass strength, thus a stable table edge is still required to insure the initial break begins at the scratch. Hence, even with a cutter used, without forcing the break to begin on the crack the glass will not likely break on the crack when force is applied. Random short scratches cannot propagate cracks and have no meaningful effect on the strength of the glass. You can polish them out for aesthetic purposes.

Even scratches as deep as those used to cut glass, when short with random directions, will not effectively reduce the strength of the glass. Glass cutting depends on a continuous propagation to control the break location. This crack propagation effect is not dependent on any significant reduction of glass strength, thus a stable table edge is still required to insure the initial break begins at the scratch. Hence, even with a cutter used, without forcing the break to begin on the crack the glass will not likely break on the crack when force is applied. Random short scratches cannot propagate cracks and have no meaningful effect on the strength of the glass. You can polish them out for aesthetic purposes.

Thanks for all the replies! I myself was not too worried but my wife is a huge worrywart. She has a mental image of walking past the tank (its 110 gallons) and a fish tapping the scratch and exploding the tank outward at her. This spring I am going to tear it down for a good cleaning and I'll try a quick polish.

Dean

This spring I am going to tear it down for a good cleaning and I'll try a quick polish.

*nods* Just expect for that "quick polish" to take about two to three hours with a hand tool. The article I linked to above mentioned it taking a couple hour-long attempts.