Kinesthesia, there are some things about kalkwasser a consciencious aquarist may want to be aware of.
I think the thing of most importance is to be careful that your system "vents" carbon dioxide by aggresive water motion (so you break up that tough skin the water molecules form) at an air water interface (the water's surface in your display is a huge example of air-water interface that can vent a lot of carbon dioxide). The reason is this: Kalkwasser is composed of calcium hydroxide (one calcium ion, one hydroxyl ion (hydroxyl is composed of oxygen and hydrogen). When kalkwasser is added to your system, the calcium and hydroxyl become separated, forming ions. While the calcium can be used readily by the corals, the hydroxyl ions bond with carbon dioxide to form carbonates.
The concentration of carbonates (and bicarbonates) in our water is what we term as alkalinity, and it is generally what provides insurance against a pH drop in our water. Now this sounds like a good thing, and it is, however, if while using kalkwasser you don't adequately vent carbon dioxide, the carbonate concentration in your water can become saturated. Once the concentration climbs beyond saturation, the carbonates fall out of solution, termed as precipitation.
However, they don't fall out of solution as ions, they bond with calcium ions, and precipitate out of your water as calcium carbonate. This process can compact and solidify your sandbed, and this may make it unmanageable by your detritovorous organisms, thus allowing bacteria in the sand to buildup a lethal concentration of
hydrogen sulfide, which may leach into your bulk water. This process of precipitation also removes the calcium from your water making it useless to flora and fauna that need it in ionic form.
So yes, you can add too much, but this can be prevented by much testing initially, and testing subsequent to adding new calacareous specimens in order to assure absorption of calcium corresponds to how much you add.
Cheers,
Chris
[ 07-01-2001: Message edited by: galleon ]
