Calcium and Magnesium are often present in soil as carbonates (e.g.: dolomite), sulfates (in arid regions) and silicates. They are necessary nutrients for plants since they have an important role in plant metabolism and growth. They can be removed from soil by leaching (for instance in acidic soil of humid regions) or by crop production; a deficiency of calcium and magnesium in soil will manifest itself in stunted growth and in yellow and deformed leaf tips. On the other hand, soil with an excess of calcium and magnesium will lock up other necessary micronutrients, making them unavailable to plant roots (e.g.: available phosphorus forms an insoluble salt with calcium at pH values above 7.5, thus decreasing the efficiency of applied phosphorus fertilizers).
The HI 38081 test kit determines calcium and magnesium in irrigation water via a titrimetric method. The indicator chelates with the calcium and magnesium ions to form a red colored complex. As EDTA is added, calcium and magnesium complex with it, and the reaction endpoint is indicated by a change in color of the indicator from red to blue.
Order Information:
HI 38081 test kit comes with 30 mL Ca & Mg reagent, 120 mL EDTA solution (2), 10 mL calmagite indicator, demineralizer bottle for 12 L, 50 mL calibrated vessel, 1 mL plastic pipette, 3 mL plastic pipette and 1 mL syringe with tip.
Manual: Download
| Method | Titration | |
| Range | >0.0 meq/l | |
| Smallest Increment | 0.2 meq/l | |
| Chemical Method | EDTA | |
| Number of Tests | approx. 100 | |
| Weight | 671 g |
HI96821 Sodium Chloride - Digital Refractometer Portable
HI755 Checker HC ® - MARINE Alkalinity (dHK)
BL983320-1 EC Mini Controller 0 to 199.9 µS/cm, 230V
HI93754B-25 Medium Range COD Reagent (0 to 1500 mg/L)
HI7040L DO Solution, 500 ml
HI96801 Sucrose - Digital Refractometer Portable
HI200M 1L Magnetic stirrer with stainless steel cover plate, 230V
HI7042S Refilling Solution for Galvanic Probe, 30ml
BL983317-1 EC Mini Controller upto 10.00 mS/cm, 230V
HI717 Checker HC ® - Phosphate, HR
HI98130 COMBO Tester for pH/EC/TDS/C° up to 20 mS, waterproof
Calibration Standard HI 701 Checker HC ®
HI1292D - pH Electrode (Soil)
Reagents for HI 708 Checker HC ®, 25 Tests
น้ำยามาตรฐานสอบเทียบ
HI3834 - CTK Iron Test Kit
HI147-00 Thermometer Checkfridge™ (°C)
Calibration Standard HI 721 Checker HC ®
Chlorine Removal
HI5009 - 9.00 pH@25°C - TQ - 500ml
Multiparameter pH/ORP/EC/Pressure/Temperature Waterproof Meter
Checker® Plus pH Tester
FC232D - Foodcare pH-Elektrode für HI 99161, DIN, 1 m Kabel (Fleisch)
Reagents for HI 707 Checker HC ®, 25 Tests
BL983329-1 TDS Mini Controller 0.0 to 999 mg/L (ppm) - 230V
Reagents for HI 701 (Free Chlorine), 25 Tests
BL10 Black Stone Dosing Pump 10.8 lph 3 bar
HI9829 Multiparameter pH/ISE/EC/DO/Turbidity Waterproof Meter with GPS option
HI145-20 Thermometer (°C) with T-shaped (300mm)
HI991301 Multiparameter pH/EC/TDS/°C - EC to 20.00 mS
HI93102 Water Analysis Meter (with Turbidity up to 50NTU)
เครื่องควบคุมค่าความนำไฟฟ้า
HI38040 CTK Iron Medium Range 
