"Dave" wrote in message ups.com...
I've been considering using Mrs. Wage's Pickling Lime as a substitute
for powdered kalkwasser, which is more expensive, and Mrs. Wage's
Pickling Lime even comes in a nifty resealable plastic container now.

I got the chemical composition of MWPL ... anyone see a problem here
after the CaOH2? Percentages seem pretty low but just want to make
sure.

97.4% Ca (OH)2
1.8% Ca03
1% Magnesium & Alkali Salts
.4% Acid Insoluble Substances
.02% CaS04
.03% Fe203
.2% Al203
.01% C02

Everything below 1% one could interprete as just dirt.
Such foreign substances will exist in any chemical product.
You could ask your kalkwasser powder manufacturer
how much Ca(OH)2 is in 100gram of their product
and I bet you it could be something around 97-98%
or less. It will simply mean that the rest is "dirt" again...
Products in aquarium trade are not ment to be used
in analitical chemistry lab so they are not chemicaly
"pure" substances.