- Contains calcium, strontium, and magnesium in the same ionic ratios found in aragonite. This unique feature increases the usefulness of Kalk+2 to reef-building invertebrates such as corals, clams, calcareous algae, etc.
- Provides temporary alkalinity and helps maintain pH within the desired range when used as directed.
- Adds no conservative elements, such as chloride, to the aquarium.
- Improves upon the industry-standard powdered calcium supplement over the past three decades.
- Formulated by a marine scientist.
Calcium, magnesium, and strontium are required for the formation of aragonite, the skeletal material of reef-building invertebrates such as corals, clams, tube worms, and their respective allies. Brightwell Aquatics Kalk+2 provides these elements and may also be used to help regulate pH in reef aquaria. Kalk+2 does not contain chloride salts, which is a strong point for some hobbyists. The use of kalkwasser-type products remains very popular with many seasoned hobbyists, regardless of innovations in calcium-delivery methods.
Instructions and Guidelines
Kalk+2 is intended for use by experienced hobbyists who are familiar with kalkwasser (calcium hydroxide-based) products. The calcium concentration (”[Ca2+]”) and pH in the aquarium should be determined by using an accurate test kit prior to supplementing. Do not add this product directly to an aquarium without diluting in water as directed, and do not overdose; it must be added in a controlled fashion with a dosing device. Create a stock solution by dissolving 6 grams (~1 tsp) of Kalk+2 in 1 US-gallon of fresh water (preferably purified) and allowing at least one hour for any settling to occur; each ml of the saturated sol’n will increase the [Ca2+] in 1 US-gallon (3.785 L) of water by 2.3 ppm, strontium concentration by 0.04 ppm, and magnesium concentration by 0.06 ppm. This solution must then be dosed/dripped into the aquarium at such a rate that salinity does not fall below 1.021 g/cm3 and pH does not increase by more than 0.1 every hour, nor is it ever allowed to exceed a value of 8.5. Dosing at night when pH in a reef aquarium is naturally depressed is often performed to avoid exceeding the maximum allowable pH value. If the [Ca2+] in an aquarium is gradually dropping despite using this product as directed, the rate of evaporation may be insufficient or pH may be too high to dose sufficient calcium to compensate for the rate of removal by reef-building aquarium inhabitants and/or undesirable chemical reactions. In this case, a secondary calcium supplement may be needed to occasionally re-establish the natural seawater concentration of calcium in the aquarium.
Caution: Calcium hydroxide is a caustic material; if inhaled, remove to fresh air, and in case of contact flush skin and/or eyes with fresh water for 15 minutes. Drink 16-oz. fruit juice if swallowed and seek immediate medical attention. Keep out of reach of children. Not for human consumption.
Guaranteed Analysis (by weight)
Calcium (min) 54.20% (542,000 ppm), Strontium (min) 1.00% (10,000 ppm), Magnesium (min) 0.15% (1,500 ppm)
Calcium hydroxide, Strontium hydroxide, Magnesium hydroxide.
Brightwell Aquatics Aquarium Supplies
The goal of Brightwell Aquatics is to provide the absolute highest quality, scientifically-sound products and customer service of any aquarium water care manufacturer, and to do it all in a straight-forward and honorable fashion. All Brightwell products are formulated by marine scientists with a passion for the aquarium hobby. They utilize the highest purity ingredients in concentrations that provide the most use to hobbyists. Nearly all Brightwell Aquatics products are over 99.9% pure. The usage guidelines of Brightwell Aquatics products are written in plain language but the company is always available to answer consumer questions. All products are lot numbered for quality control and customer service.
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