What is Calcium?

Calcium, scientific formula as Ca, is a very important element for most animal life, especially for corals and shellfish.

It is the main cause of hard freshwater. Certain species of freshwater fish require certain levels of calcium. It is also the main ingredient in limestone, shellgrit and coral. Calcium, as an element, does not affect pH.

Normal Levels

In seawater the level of calcium at normal specific gravity is 383ppm. If seawater is used at a lower specific gravity than normal, levels of calcium will be proportionally less. For freshwater aquariums please check appropriate text books, however all Aquasonic Water Conditioners have exacting amounts of calcium to suit designated species.

Calcium Build Up

It is most important in both fresh and saltwater aquaria to set the levels of calcium when establishing the aquarium and then hold the appropriate levels by the addition, if necessary, of calcium in prescribed amounts. The use of shellgrit or coral rubble as a substrate or filter material can cause calcium levels to continually rise, to unacceptable levels.

Reef Aquariums

A maximum level of 450ppm is recommended for Reef Aquariums. If the level is taken above this then Carbonate Hardness levels, the main reason for stable pH, may be affected. The calcium would precipitate the carbonate as calcium carbonate. Calcium is used by calcareous algae, corals and shellfish, so in some situations, levels may require constant replenishment.

To Set Calcium Levels

In salt water, maintain levels with Aquasonic Ocean Nature Sea Salt. Normal specific gravity = 383ppm. Raise calcium in saltwater with Aquasonic Calcium-Sup. In freshwater, maintain levels with Aquasonic Water Conditioning Salts.

Directions for Use:

To determine Calcium in Salt or Fresh Water. Read Instructions Carefully Before Use. The test kit has a dual range. Measurements can be made in steps of 25ppm or 50ppm.

Note:

Seawater usually contains 350-450ppm of calcium.

To Test in 25ppm:

1. Rinse a clean test tube several times in the water to be tested and fill to the 10ml mark.
2. Add 1 level scoop of Reagent A and 4 drops of Reagent B.
3. Shake until powder dissolves (about 1-2 minutes). Solution will turn bright red if calcium is present.
4. Immediately add Reagent C a drop at a time, swirling to mix after each addition. Keep count of the number of drops until colour changes to the end point (see chart) and multiply this by 25 to give calcium in ppm.

To Test in 50ppm:

1. Rinse a clean test tube several times in the water to be tested and fill to the 5ml mark.
2. Add 1/2 scoop of Reagent A and 2 drops of Reagent B.
3. Shake until powder dissolves (about 1 minute). Solution will turn bright red if calcium is present.
4. Immediately add Reagent C a drop at a time, swirling to mix after each addition. Keep count of the number of drops until colour changes to the end point (see chart) and multiply by 50 to give calcium in ppm.

*This colour chart provides a basic guide only. Colours may vary according to various water conditions.