shawmutt
Aquarium Advice Addict
LOL, in looking up some of my info, I found that it is spelled arAgonite--I learn something new every day 
Vinegar, or acetic acid, is supposed to react with the sand. Just now, as an experiment (because I never actually have done it before), I put some of my sand on a shallow dish and added white distilled vinegar to it. It definitely bubbles, like glass of soda. If your sand isn't bubbling, perhaps you are not using a strong enough vinegar (mine is 5% acidity according to the label)--or the limestone doesn't react as strongly as the aragonite. Upon research of the OldCastle website, I found that they have mostly quartz sand. Does it say "aragonite" or "contains no silica" on the label anywhere?
The local stuff is mined from a limestone quarry, limestone and coral are the same substance--calcium carbonate, or CaCO3.
Some here have also pondered whether the sharper, crystalline edges of quartz irritate fish's gills when they dig through it. Now that I think about it, the sunfish, a local cichid, digs in quartz sand when constructing their nests, so perhaps using quartz sand is ok in this matter.
Vinegar, or acetic acid, is supposed to react with the sand. Just now, as an experiment (because I never actually have done it before), I put some of my sand on a shallow dish and added white distilled vinegar to it. It definitely bubbles, like glass of soda. If your sand isn't bubbling, perhaps you are not using a strong enough vinegar (mine is 5% acidity according to the label)--or the limestone doesn't react as strongly as the aragonite. Upon research of the OldCastle website, I found that they have mostly quartz sand. Does it say "aragonite" or "contains no silica" on the label anywhere?
The local stuff is mined from a limestone quarry, limestone and coral are the same substance--calcium carbonate, or CaCO3.
Silica, or quartz sand, is by far the most prevelent sand on beaches. It is most desirable in fish tanks that have a low pH requirement, as quartz resists chemical reactions. Some people also like it because the grains are more uniform in size. However, wet quartz sand compacts much tighter than the "fluffier" argonite sand. This may cause problems with anerobic bacteria and ods if the sand bed is not maintained properly.Sparky said:
Some here have also pondered whether the sharper, crystalline edges of quartz irritate fish's gills when they dig through it. Now that I think about it, the sunfish, a local cichid, digs in quartz sand when constructing their nests, so perhaps using quartz sand is ok in this matter.
