In a message dated 4/25/03 1:35:34 PM, caw18@bak.rr.com writes: << I then mixed it with water and watched for a reaction (bubbling, ect..) There was none. Therefore I am assuming the sand is inert. >> Bubbling will occur by reaction of a stronger acid with a salt of carbonic acid (such as Calcium carbonate), releasing carbon dioxide bubbles. Sodium silicate however can be soluble enough to raise the pH but will not release carbon dioxide. Lee Harper Media, PA USA ----------------------------------------------------------------------- -- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. apisto-digest@listbox.com also available. Web archives at http://lists.thekrib.com/apisto Trading at http://blox.dropship.org/mailman/listinfo/apisto_trader