explain the vineger test on sand?

[allen1973]

I found some white play sand that looks great but don't know how it would work in the new 150 aqaurium that I have even though it says not aqaurium safe,but all playsand says that,so what do you look for in the test with vineger?

 

[thomas712]

Take a sample of your sand and test some of the sand with vinegar. If it bubbles/dissolves, it is calcium carbonate sand and should be safe to use.
Take some sand and pass a magnet over it or in it, it might come out with little metal shavings from processing, if it does I would not use it. Though I have heard of some who have with little poor effects. Iron can actually be a fertilizer for macro algae.
Thomas

 

[nereef]

yep, vinegar is a great way to dissolve limestone. good post thomas