The water isn't so much green, but murky. Not clear.

"Hal" wrote in message
news
On Sat, 5 May 2007 08:43:20 CST, "Henry & Carolyn"
wrote:

When do you start putting alum in the pond? Do you have to wait for the
water to warm up?

Why? You leave me puzzled, because I don't have green water when it
is cold. I only use alum (aluminum sulfate) to kill algae and help
coagulate floating particles to the bottom. It is not a permanent
cure for algae, only temporary. Alum will kill it and clump it on the
bottom, but you must remove it or it decays into nutrients that
promote more algae growth.

Alum should be used with a caution that it is acidic. It will remove
some of the KH. (KH is the carbonates in the water that keep the pH
stable.) Baking soda is a quick, safe and temporary cure for KH loss.
Suggested dose 1/3 pound per 1000 gallons. That will raise KH by 20
ppm. or about 1 degree.

Regards,

Hal