lime in aquarium water

["Kinney, Travis" <kinney at pdtarchs_com>]

Ok, so my experiment with manmade rock formations has led me to figure out
what effects lime has in the aquarium water. Thankfully there are no fish or
plants in this tank yet as I am in the process of setting it up. In my new
tank I want a steep slope in one corner. Instead of relying on aquarium
gravel to hold a steep slope I took some advice from reef keepers and made
my own rock formation. I used a mix of lava rocks and gravel mixed with
Portland cement. Unfortunately all, I had was Portland cement with LIME. My
plan was to tie to some fishing line and lower into a stream nearby and let
it leach for a month or so. But I didn't feel like chipping a hole through
the ice to get at the water! The stream is open now, BUT my rock form is in
my tank with driftwood above it that is adhered to the glass. Now, after a
few days of the rock form being submerged, I felt the glass and it was
gritty, like it was frosted glass. I assumed it was lime leached from the
rockform that was sticking to the glass. A razor scrapes it off. I'm doing
water changes, and running a filter with charcoal. The leaching has slowed,
and I have time to wait. However, I was just curious as to what lime does to
the water and how toxic it is to plants? Are there plants that can absorb
it? I hope it can't etch my aquarium glass, can it?

Here's the rockform I made:
http://www.fishlinkcentral.com/photos/showphoto.php?photo=969

-Travis