Reef Kalkwasser 500GRS

Reef Kalkwasser™ - 500g - SEACHEM

- Highly pure calcium hydroxide
- Ideal for increasing calcium in top-off water
- Increases pH without affecting carbonate alkalinity

Overview

Reef Kalkwasser™ is a pure calcium hydroxide with unmatched purity and solubility characteristics. Calcium hydroxide is used to prepare limewater (kalkwasser) solutions that maintain calcium concentrations at natural seawater levels. Kalkwasser solutions maintain calcium directly and carbonate alkalinity indirectly. However, its ability to fulfill these functions depends on the evaporation rate and CO₂ concentration. If these two factors are insufficient, you can provide additional calcium with Reef Advantage Calcium™, Reef Complete™, or Reef Calcium™, and carbonate alkalinity with Reef Builder™ or Reef Carbonate™ (do not mix these directly with a kalkwasser solution).

Although Reef Kalkwasser™ is a high-purity and economical limewater mix, beginners or those who do not have much time to devote to their system may prefer to use other less involved methods to maintain proper ionic concentration levels.

Sizes: 250g, 500g, 1kg, 2kg

Instructions

Never add this product directly to the tank. Add 3g (1 teaspoon) to 4L (1 US gallon) of water and mix to dissolve.

If using pure water, a fully saturated solution is prepared by adding 6g (2 teaspoons) to 4L (1 US gallon).

Drip this solution into the tank.

Monitor pH and carbonate alkalinity.

Adjust the addition rate to maintain a stable pH (8.3–8.4).

Notes: Adding 4L (1 US gallon) of a saturated kalkwasser solution to 150L (40 US gallons) will increase calcium by 24 mg/L.

Always use only the clear supernatant (upper solution) and do not allow undissolved material to enter the aquarium.

Keep this container tightly closed when not in use and minimize solution/air contact to avoid calcium carbonate formation/precipitation.

FAQ

After mixing a limewater solution, are the sediments left at the bottom of the container reusable until fully dissolved, or should they be discarded?

It is very likely that the excess calcium hydroxide (kalkwasser or limewater) that has settled at the bottom will not dissolve and will need to be discarded. The longer it sits, the more likely the hydroxide is to convert CO₂ in the water to carbonate. This carbonate will form a precipitate with calcium (calcium carbonate) and will not dissolve.