On Nov 8, 2:13*pm, zxcvbob wrote:
mj wrote:
On Nov 8, 1:55 pm, zxcvbob wrote:
mj wrote:
Where can I buy a pound or two of this and not have the shipping be
crazy? Where could I buy it in say a local store? I have all the other
chemicals for my hydroponics except this one and I don't want to have
to buy a ton.
MJ
Plaster of Paris. *You'll probably have to hydrate it to make it useful.

Bob

As in every elementary school *project plaster of Paris? *I need it in
a dry form mixed with all the other stuff and then it is dissolved
into the water system.

Yes. *But you want hydrated calcium sulfate, CaSO4·2(H20), and Plaster
of Paris has been dehydrated to 2(CaSO4)·H2O. *So you'll probably want
to add excess water, let it harden, then pulverize it.

Bob

I failed chemistry, why harden it first, because just adding it to the
water in the system it will harden there? Thanks for all the help