"CLAIREBARE01"  wrote in message
news:20030418124034.18820.00000109{at}mb-m27.aol.com...
> hi avisinai!
> i don't know if this will help,  but have you heard of the vinegar test?
> if you drip vinegar onto the stones which you want to put in your tank and
the
> vinegar has no reaction then you can use them... if it starts to react ie
> bubble do NOT use them.
> i hope that this might help you even though it only answers half of your
> question!!
> love clairebear.

Vinegar is a weak acid, anything that fizzes with vinegar probably has
carbonates in it and will raise the pH.  That said, it is a very weak acid
and won't get a reaction from a hard dense limestone which would still raise
the pH.

If you can't find some HCl (Hydrochloric or muriatic acid)  .. somewhere
around 10 molar is what geologists are supposed to use (10% is close enough)
try scratching the pebble.  Many dolomites will not react to the acid test
unless you scratch them to produce a bit of powdered rock. Most pharmacies
should to be able to make up a weak HCl solution, or you local high school
chemistry teacher might be willing to help. If you can get it to scratch,
put warm vinegar on the material produced.

It comes to mind, you might just fill a bucket with water from you next
water change, test the pH, then add the stones, check the pH over a few days
to see it anything changes significantly.  You might want to do two buckets,
one without adding stones as a standard just to make sure something wasn't
happening to the water just sitting.

Of course, it depends on your fish, some might do better is high pH water.

Bob
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