On 26 Nov 2006 11:47:47 -0800, "Frank" wrote:

Calcium buildup. If it is a light case a product like clr might remove it.

For a heavy layer reduce the water level to the lowest point and use about a
quart of muriatic acid with the window open. The fumes are nasty.

Be very careful if you use the acid!!!!!!!!!!!!!!!

Vinegar may also do it and it's obviously safer to use.

Vinegar is excellent for removing calcium spots on cars hit by
sprinklers with hard water.

--
Oren

"Well, it doesn't happen all the time, but when it happens, it happens constantly."