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Aquarium Calcium & Aquarium Kalkwasser Additives
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Brightwell Aquatics Calcion Liquid Calcium Supplement, 2 liters Brightwell Aquatics Calcion Liquid Calcium Supplement, 2 liters

Product Code: RBA01011
Brightwell Aquatics Calcion Liquid Calcium Supplement is a highly-concentrated ionic calcium solution. 2 liters.

Our Price: $31.00
In Stock
Brightwell Aquatics Calcion Liquid Calcium Supplement, 250 ml Brightwell Aquatics Calcion Liquid Calcium Supplement, 250 ml

Product Code: RBA01009
Brightwell Aquatics Calcion Liquid Calcium Supplement is a highly-concentrated ionic calcium solution. 250 ml.

Our Price: $6.30
In Stock
Brightwell Aquatics Calcion Liquid Calcium Supplement, 500 ml Brightwell Aquatics Calcion Liquid Calcium Supplement, 500 ml

Product Code: RBA01010
Brightwell Aquatics Calcion Liquid Calcium Supplement is a highly-concentrated ionic calcium solution. 500 ml.

Our Price: $10.90
(Out of Stock)
Brightwell Aquatics Calcion-P Dry Calcium Supplement, 200 grams Brightwell Aquatics Calcion-P Dry Calcium Supplement, 200 grams

Product Code: RBA01103
Brightwell Aquatics Calcion-P Dry Calcium Supplement is a high-purity powdered calcium. 200 grams.

Our Price: $8.80
In Stock
Brightwell Aquatics Calcion-P Dry Calcium Supplement, 400 grams Brightwell Aquatics Calcion-P Dry Calcium Supplement, 400 grams

Product Code: RBA01104
Brightwell Aquatics Calcion-P Dry Calcium Supplement is a high-purity powdered calcium. 400 grams.

Our Price: $13.70
In Stock
Brightwell Aquatics Calcion-P Dry Calcium Supplement, 800 grams Brightwell Aquatics Calcion-P Dry Calcium Supplement, 800 grams

Product Code: RBA01105
Brightwell Aquatics Calcion-P Dry Calcium Supplement is a high-purity powdered calcium. 800 grams.

Our Price: $18.00
In Stock
Brightwell Aquatics CoraLazarus High-Purity Calcium Media, 1000 grams Brightwell Aquatics CoraLazarus High-Purity Calcium Media, 1000 grams

Product Code: RBA01411
Brightwell Aquatics CoraLazarus High-Purity Calcium Media is a high-purity natural mineral that may be employed in traditional calcium reactors, or even blended in to pre-existing aquarium substrate, to gradually increase and maintain the calcium concentration and alkalinity in marine aquaria. 1000 grams.

Our Price: $8.00
In Stock
Brightwell Aquatics CoraLazarus High-Purity Calcium Media, 5 Kg Brightwell Aquatics CoraLazarus High-Purity Calcium Media, 5 Kg

Product Code: RBA01412
Brightwell Aquatics CoraLazarus High-Purity Calcium Media is a high-purity natural mineral that may be employed in traditional calcium reactors, or even blended in to pre-existing aquarium substrate, to gradually increase and maintain the calcium concentration and alkalinity in marine aquaria. 5 Kg.

Our Price: $30.90
In Stock
Brightwell Aquatics Kalk+2 Kalkwasser Supplement, 1.8 KG (4 lbs) Brightwell Aquatics Kalk+2 Kalkwasser Supplement, 1.8 KG (4 lbs)

Product Code: RBA01116
Brightwell Aquatics Kalk+2 Kalkwasser Supplement 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. 1.8 KG (4 lbs).

Our Price: $48.80
In Stock
Brightwell Aquatics Kalk+2 Kalkwasser Supplement, 100 grams Brightwell Aquatics Kalk+2 Kalkwasser Supplement, 100 grams

Product Code: RBA01113
Brightwell Aquatics Kalk+2 Kalkwasser Supplement 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. 100 grams.

Our Price: $7.00
In Stock
Brightwell Aquatics Kalk+2 Kalkwasser Supplement, 225 grams Brightwell Aquatics Kalk+2 Kalkwasser Supplement, 225 grams

Product Code: RBA01114
Brightwell Aquatics Kalk+2 Kalkwasser Supplement 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. 225 grams.

Our Price: $10.30
In Stock
Brightwell Aquatics Kalk+2 Kalkwasser Supplement, 450 grams Brightwell Aquatics Kalk+2 Kalkwasser Supplement, 450 grams

Product Code: RBA01115
Brightwell Aquatics Kalk+2 Kalkwasser Supplement 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. 450 grams.

Our Price: $14.20
In Stock
   
 

Kalkwasser Overview

Kalkwasser has been called the king of aquarium additives. But what is it, what does it do, and why would you want to add it to you aquarium?

Kalkwasser is water mixed with powdered lime or calcium hydroxide. The kalkwasser additives aquarists purchase are made of dried powder or kalk, and this powder is mixed with purified RO/DI water. Two Little Fishes Kalkwasser and Brightwell’s Kalk +2 are recommended kalkwassers.

What Does Kalkwasser Do?

-Adding kalkwasser will cause the pH of your aquarium to rise because it’s a base. Keeping a proper high pH of 8.2-8.4 can help your corals grow faster and help stop the growth of unwanted algae.

-Kalkwasser raises calcium and alkalinity. Calcium and alkalinity are what corals, snails, and clams use to build their bodies. In a reef aquarium the calcium and alkalinity levels drop as the animals inside the tank grow. Using kalkwasser to ensure calcium and alkalinity are at proper levels can dramatically increase the growth of your corals and invertebrates.

-Adding kalkwasser to your aquarium removes phosphates from the aquarium water by causing it to precipitate out of solution. Phosphate can fuel unwanted algae growth or cause corals to grow brittle skeletons. Using kalkwasser can help eliminate or reduce the need for other phosphate removers such as Phosban or Phosphate RX.

How Do You Use Kalkwasser?

Kalkwasser is sold as a powder. You first must mix this powder with purified RO/DI water. You then can add it to the aquarium. It’s very important you don’t add too much at once. Kalkwasser has a very high pH of 12.3 which can raise the pH of your aquariums so fast that it can harm the fish and corals inside. To add the solution slowly there are a few methods.

Kalkwasser Reactors – Kalkwasser reactors such as the Aqua Medic KS1000 and the Two Little Fishies KW Reactor are the most efficient way to use kalkwasser. They can be used in conjunction with either a dosing pump or an auto top off. These reactors constantly stir kalk powder into water making sure that the water exiting the reactor has the maximum amount of kalk powder dissolved in it. Kalk reactors also reduce the maintenance associated with the other methods as kalk powder only needs to be added every few months.

Dosing Pumps – Dosing pumps include the IceCap Dosing Pump, Milwaukee MC720 Dosing Pump Kit, and the Neptune DOS. These will all pump kalkwasser very slowly into your aquarium. And in the case of the Neptune DOS and Milwaukee Dosing Pump Kit, the pump will shut off if the aquarium pH ever rises too quickly.

ATO Reservoirs – If you have an auto top off such as the IceCap ATO or SpectraPure Liquid Level Controller you can add kalk powder to the reservoir of top off water your ATO draws from. This will ensure that only a small amount of kalkwasser is added at a time.

Manual Drip – The simplest way to dose kalkwasser is to slowly drip the solution into your aquarium. This is usually done with airline tubing and a ball valve. We do not recommend this approach because if the drip rate is too fast your aquariums pH may rise too quickly and harm the animals in your aquarium. Additionally, a new solution of kalkwasser needs to be mixed up every day which can be labor intensive.

Alternatives to Kalkwasser

If this all seems like too much work an alternative to kalkwasser is the two part method which utilizes two separate solutions: one with calcium and one with alkalinity, such as ESV B Ionic. These chemicals can simply be poured into the aquarium without a risk of raising the pH too high. However, two part additives will not give you the elevated pH that properly dosed kalkwasser will. It will also not precipitate phosphate, and it will be significantly more expensive in the long run.