Muratic acid. Sold at Lowe's and most other home improvement stores.
Usually in with the paint thinners etc. I have used it for years.

"Barbara Yanus" wrote in message
.. .
Hi,
I just got my pool looking good again. From all the rain that we had,
and no swimming, the pool turned a bright shade of green. It almost
looked
like a pond instead of a pool. I put two packages of shock in it, and
some
PH, and it's just about cleared up. Problem is, when I tested the water,
now it might have too much PH, the test kit said to add acid. My question
is, what household product can I use to put more acid in the water. I
remember someone posted a sight one time, that listed household products
could be used instead of buying those expensive ones from the pool stores.
Can anyone help me?

thanks

Bebra1

NE PA
zone 6b