Test Kit & Measuring instruments

Salinity and Parameter test kits

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  • American Marine Pinpoint Digital Calibration Thermometer

    • Resolution to one-tenth of a degree (00.1 F or 00.1 C)
    • A Lab Quality instrument.
    • Fahrenheit or Celsius display
    • 2 Year Battery Life
    • 10 Cable
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  • Dosetronic



    Same footprint as the Alkatronic, Dosetronic will be around the half height of an Alkatronic.


    Customizable to have the 10 luer connections on either side

    Communication with Alkatronic:


    Controlled by:

    Wifi based app, and cloud.


    5, stepper based


    0.05 ml





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  • Milwaukee digital refractometer for seawater



    • Range: 1.000 – 1.114
    • Resolution: 0.001
    • Accuracy: 0.002
    • Measurement Time: Approximately 1.5 seconds
    • Battery Type: 1 x 9V (included)

    Key Features

    • Dual-Level LCD Display
    • Automatic Temperature Compensation (ATC)
    • Easy Setup and Storage
    • Battery Operation with Low Power Indicator
    • Automatically Turns Off After 3 Minutes of Non-Use
    • Stainless Steel Sample Well and Flint Glass Prism
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  • RedSea Foundation Pro Multi Test Kit


    Reef Foundation Pro Multi Test Kit Package size/volume:

     Test Name Element Accuracy Range Test Type No. of test
     Calcium Pro Ca 5 ppm Titration 75
    KH/Alkalinity Pro KH 0.05 meq/l Titration 75
    Magnesium Pro Mg 20 ppm Titration 75
    Read more
  • RedSea Seawater Refractometer


    Main features of Red Sea’s Seawater Refractometer include:

    • Directly reads the absolute salinity of seawater at 25°C/77 0F  ( No need for seawater or temperature compensation factors)
    • Specifically designed for the ionic content of seawater (NSW) for more accurate salinity measurement (industry standard refractometers are calibrated for salt brine ).
    • Calibrated for seawater (NSW) at 25oC/77oF, the normal temperature range for reef aquariums
      (most standard refractometers are calibrated at 15oC/59oF ).
    • Easier to read, higher resolution display, focussed to the relevant range for reef aquariums of up to 40ppt
    • Includes Integrated Automatic  Temperature Compensation (ATC) for accurate measurement at standard ambient temperature.

    Red Sea’s Refractometer display

    The PPT scale on Red Sea’s Seawater refractometer is calculated using an algorithm for seawater and therefore will give a reading of the Absolute Salinity of seawater.

    The PPT scale on regular salinity refractometers are calculated using an algorithm for Brine. Using a Brine refractometer for Seawater will give an error of approximately 1.5ppt in the salinity reading.

    Red Sea’s Seawater refractometer red sea seawater refractometer. salinity test for saltwater aquariums
    Red Sea’s Seawater Refractometer display
    Typical Salinity Refractometer display

    About Salinity

    Salinity is a general term describing the concentration of salt in water. However, solutions of different type of salts have different refractive indexes.

    Brine is a solution of Sodium Chloride (table salt) that contains 2 chemical elements.

    Seawater contains approximately 70 chemical elements that include Calcium, Magnesium, Potassium etc. in addition to the Sodium Chloride.

    Seawater and Brine of the same salinity (i.e. the same weight of salt/liter) have different refractive indexes and will give different salinity readings if measured on the same refractometer.

    Refraction & refractive index

    All transparent materials such as liquids refract (distort) light.

    All transparent materials refract light differently and have what is called a “refractive index” which means how much a particular material distorts light.

    Different concentrations of the same liquid have different refractive indexes.

    The scale of a refractometer is calculated by using a mathematical algorithm that relates the measured refraction to its concentration for a specific liquid.


    Refractive index and temperature

    The refractive index of liquids change with temperature and therefore has a major effect on measuring salinity with a refractometer.

    The algorithm for defining the PPT (and S.G.) scale for a refractometer is calculated for a specific temperature.

    PPT readings from refractometers that are not calibrated for reef aquariums (i.e. 25oC) need to be adjusted according to a conversion table to give the actual PPT at the aquarium temperature. This is often a cause for misinterpretation of refractometer readings.

    For example, using a seawater refractometer calibrated at 20oC will give a PPT reading that is approximately 1-1.5ppt lower than the absolute salinity of the same water sample at the normal aquarium temperature of 25oC.

    Therefore, Red Sea’s Seawater Refractometer calibrated at 25°C/77 0F directly reads the absolute salinity of seawater with no need for temperature compensation factor)

    ATC – Automatic temperature compensation

    Temperature is probably the biggest cause of wrong readings with a refractometer. Calibration and testing of water samples should be done after the refractometer and water sample have equalized at the correct temperature.

    Automatic temperature compensation (ATC) compensates for a few degrees of difference between the ambient temperature and the calibrated temperature of the refractometer. Larger temperature variations will give an error of approximately 1.0ppt in the salinity reading.

    ATC does not adjust the PPT reading of a refractometer to the temperature of the aquarium!

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  • Salifert Flatworm Exit


    Read all the above text before commencing with the treatment!

    • 1 drop for every 4 liters or 1 gallon.
    The dropper contains approx. 300 drops (10 ml). The dropper cap holds approx. 90 drops.
    So 1 cap full is good for 360 liters or 90 gallons.

    Add it in a high flow area of the tank. If you want to treat a refugium only and if it’s volume is too small for using a powerhead then mixing should be done manually.

    • It should start to work within 30 minutes.

    • If within 45 minutes no visible death of flatworms occurs add 50% more.

    • As soon as the flatworms start to die commence with the activated carbon to take out any toxic body fluids. Also see the above given important remarks.

    • After an hour or so you can turn any UV or ozone on again.

    Keep out of the reach of children! Only for aquarium hobby use


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  • Alkatronic – KH/Alkalinity controller


    IMPORTANT: iOS or Android App Required (Android requires Bluetooth 4.2 or above)

    • Maintains and Controls dKH Levels
    • Capable of Measuring every 2-12 hours
    • WiFi / Bluetooth Connectivity
    • Cloud Server Function
    • iOS or Android App (Android requires Bluetooth 4.2 or above)
    • High Precision and easy to calibrate Stepper and DC Motors
    • pH Based Titration Method
    • dKH Measuring Range: 4.48 – 15.40 dKH
    • Direct Control 3rd Party Calcium Dosing Systems (Calcium Reactor or Balling)
    • Compatible with 3rd Party Aquarium Controller (ie: Apex, GHL) via BNC Connector
    • Hardware Ready for upcoming DOSETRONIC (our new dosing station)
    • Low Maintenance

    Alkatronic is an all-in-one product for serious reefers to automatically monitor and stabilize alkalinity for your reef system. The standalone product works straight out of the box without the need of any additional dosing pump, computers or other equipment to use.

    The Alkatronic automatically monitors the alkalinity (KH) in your tank, as well as corrects any deviations within the user’s settled reference intervals by dosing carbonates from its own dosing pump or by activating a Bluetooth Smart Outlet (included).

    Calcium Reactor users can benefit from precise control over the CO2 to the Ca reactor through the included Bluetooth Smart Outlet controlled by the Alkatronic. As long as the dKH is below the set value, this outlet will be on and let the calcium reactor be controlled by the pH controller.  If the value rises above, it will override the ordinary regulatory equipment and shut off the CO2 until the dKH is back within range.


    Alkalinity is a means of quantifying the stability of pH in aquarium water. It is a measure of the concentration of various negatively charged ionic compounds (anions) such as carbonates, bicarbonates, borate and hydroxides in the aquarium water. Although a simple and affordable test, user error and time is taken out of the equation so that one can rest assured that their reef aquarium is safe and stable.


    Alkalinity maintenance is a critical aspect of coral reef aquarium husbandry. If left unchecked, alkalinity can drop below a critical level and pH begins to fluctuate more wildly than the suggested daily pH shift of +/-0.2 for marine aquaria, causing stress to livestock. In a marine aquarium, the desired alkalinity is usually between 7° and 10° dKH (German Carbonate Hardness).

    The Alkatronic makes it possible to monitor the buffering capacity and automatically manage KH levels of your aquarium water in a simple all-in-one device.

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  • D-D True Seawater Refractometer


    Easier to Read & ATC

    Easier to Read

    One of the other problems with most refractometers is that the scale displayed normally reads from 0-100ppt when we are really only interested in the region from 30-40ppt. Our new Seawater Refractometer has therefore been specifically designed to read from 0-40ppt which gives you 2.5 times the resolution of a normal 0-100 scale.


    Auto Temperature Compensation (ATC)

    There is a lot of misunderstanding concerning the way the ATC feature works and its effect on the refractometer at different ambient room temperatures.

    Salinity is a measurement of a mass of salt in a mass of water and therefore does not vary with temperature however a refractometer does not measure salinity directly but measures the refractive index which is then displayed as salinity. The refractive index of a solution does vary with temperature therefore the reading that you measure with a refractometer is always temperature dependant.

    An ATC refractometer has a bimetal strip inside the instrument that moves the reading scale as the temperature changes to compensate for the change in refractive index. What people do not generally understand is that it is the temperature of the instrument and not the water temperature that is important as the small sample of water used for testing will equilibrate within seconds to the temperature of the refractometer.

    Once correctly calibrated at the set calibration temperature of 20oC the refractometer can then be used in environments where the ambient temperature and therefore instrument temperature would heat up or cool down within the range of the ATC which is between 10 and 30 centigrade.


    If you look at the scale above you will see that the refractometer states that it is calibrated at and displays the SG of seawater at 20C.

    Most salt refractometers use this temperature and will be marked 20C or 20/20. Calibration should always be carried out with the instrument at 20C which is close to the average room temperature in most cases. Allow the refractometer to stand at this temperature for 30 minutes to equilibrate.

    The D-D refractometer is designed with a copper body which is more expensive to manufacture but responds faster to ambient temperature changes than other materials.

    Note that the refractive index is also dependant on the wavelength of light too and therefore a light source closest to daylight should also be used.

    D-D refractometers are calibrated at 20C and so the calculated specific gravity at 35ppt displays a reading of 1.0266. This is the equivalent to a specific gravity reading of 1.0264 for a water sample temperature of 25C using a standard hydrometer that has a calibration temperature of 77F or 25C.

    Further reading – Salinity and its measurement article

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  • Korallenzucht – KZ Potassium Test Kit


    Potassium Test Kit for sea water tanks. For the precise determination of potassium in salt water.
    Natural potassium levels in coral reefs are 390-400mg/L.

    For potassium regulation please use Pohl’s K – Balance or K-Balance strong.

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    High sensitivity seawater alkalinity (carbonate hardness) test kit.



    approx. 50





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