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D-D Multi Test Kit

An all in one high quality test kit from D-D to monitor Calcium, Alkalinity and Magnesium in reef aquaria. These three important elements provide calcium and carbonates for Coral growth whilst also providing stable water chemistry when maintained at natural levels.

We advise that the Multi Kit is used as part of a complete testing regime that includes the D-D Phosphate, Nitrate and Iodine test kits for best results and to help monitor complete aquarium health and nutrient levels.

The D-D Multi Test Kit includes liquid tests for the three most commonly tested parameters by marine or reef aquarists, those of calcium, magnesium and alkalinity. All three parameters have a natural balance relative to each other which should be maintained to provide a healthy environment within your reef aquarium. This test kit will allow you to monitor the levels of all three parameters that they may be maintained by way of water changes, calcium reactors or scheduled dosing.

We Recommend the use of ‘balanced’ H2Ocean Pro+ salt to help maintain natural levels of these three important ions.

Product Code - TEST-CMK


Maintaining the correct calcium (Ca) level is crucial for success in marine aquaria with regard to calcification in stony corals, clams, and some soft corals.
Natural seawater has a calcium concentration of between 380-450ppm with an average of 420ppm


Maintaining correct alkalinity is crucial for success in marine aquaria as both a factor in calcification in stony corals and clams, and as a buffer to stabilise pH.

Most reef aquariums are recommended to be maintained at 7.0 – 8.4 dKH to allow additional buffering in the system to stabilise the general tendency towards falling pH. Natural seawater has a dkh of around 7.0


Magnesium is one of the most overlooked elements in the reef aquarium yet maintaining the correct magnesium (Mg) level is crucial for success with regard to calcification in stony corals, coralline algae, clams, and some soft corals. 

The correct magnesium level also allows other parameters to be stabilised effectively such as calcium and alkalinity and therefore pH

Natural seawater has a magnesium concentration of approximately 1280ppm however it is recommended that levels within the aquarium should be maintained between 1250 and 1350 depending on the salinity.