Gary, holland sand where got crushed shells wan? Good quality holland sand relatively inert.[/quote]

Uh ? sure ?? Mind my low knowledge in all this as still quite new to all this but somehow i do find some crush shells in it...perhaps only small snail shells ya....ummm but so far my tank is ok with it la...Ph is stable around 6.8-7 most of the time...

Google the word "inert" and this is what i found from wikipedia :-

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In English, to be inert is to be in a state of doing little or nothing.

In chemistry, the term inert is used to describe something that is not chemically active.

Now understand the word inert....Thanks Soyadude