{"product_id":"hanna-magnesium-checker-open-box","title":"Hanna Magnesium Checker - OPEN BOX","description":"\u003cdiv class=\"product-description\"\u003e\n\u003ch2\u003eHanna Magnesium Checker\u003c\/h2\u003e\n\u003ch3\u003e\u003cspan style=\"color: rgb(255, 0, 0);\"\u003eOPEN BOX - USED DEMO\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan style=\"color: rgb(255, 0, 0);\"\u003eMISSING REAGENTS \u0026amp; AAA BATTERY\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003eThe Hanna Magnesium Checker HI783 is a marine handheld colorimeter designed to measure magnesium from 1000 to 1800 ppm in saltwater aquariums. It provides a digital magnesium result for reef keepers who want easier, more repeatable testing than traditional colour-comparison or titration-style magnesium kits.\u003c\/p\u003e\n\u003ch3\u003eHI783 Marine Magnesium Testing\u003c\/h3\u003e\n\u003cp\u003eMagnesium helps stabilize the relationship between calcium and alkalinity in reef aquariums and supports balanced carbonate chemistry. The HI783 is designed specifically for saltwater aquarium and marine biology applications, with a range suited to typical reef and marine maintenance levels.\u003c\/p\u003e\n\u003ch3\u003eMarine Magnesium Checker Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eMeasures magnesium from 1000 to 1800 ppm.\u003c\/li\u003e\n\u003cli\u003e5 ppm resolution provides clear digital trend tracking.\u003c\/li\u003e\n\u003cli\u003eDigital readout eliminates visual colour matching.\u003c\/li\u003e\n\u003cli\u003eDesigned for saltwater aquarium magnesium testing.\u003c\/li\u003e\n\u003cli\u003eUses an adaptation of the colorimetric EDTA method with calmagite indicator.\u003c\/li\u003e\n\u003cli\u003eColour-coded syringes help make the test process easier to follow.\u003c\/li\u003e\n\u003cli\u003eLarge LCD screen provides an easy-to-read result.\u003c\/li\u003e\n\u003cli\u003eIncludes protective case for organized storage.\u003c\/li\u003e\n\u003cli\u003eWorks with Hanna HI783-25 replacement reagents.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eHanna HI783 Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003ePart Number: HI783\u003c\/li\u003e\n\u003cli\u003eProduct type: marine magnesium handheld colorimeter checker\u003c\/li\u003e\n\u003cli\u003eRange: 1000 to 1800 ppm magnesium\u003c\/li\u003e\n\u003cli\u003eResolution: 5 ppm\u003c\/li\u003e\n\u003cli\u003eAccuracy at 25°C \/ 77°F: ±5% of reading\u003c\/li\u003e\n\u003cli\u003eLight source: LED at 610 nm\u003c\/li\u003e\n\u003cli\u003eLight detector: silicon photocell\u003c\/li\u003e\n\u003cli\u003eMethod: colorimetric EDTA method using calmagite indicator\u003c\/li\u003e\n\u003cli\u003eBattery type: 1.5V AAA alkaline battery\u003c\/li\u003e\n\u003cli\u003eAuto shut-off: after 10 minutes of non-use\u003c\/li\u003e\n\u003cli\u003eOperating environment: 0 to 50°C \/ 32 to 122°F with maximum 95% RH non-condensing\u003c\/li\u003e\n\u003cli\u003ePrepared sample temperature: 22 to 28°C \/ 72 to 82°F\u003c\/li\u003e\n\u003cli\u003eDimensions: 86.0 x 61.0 x 37.5 mm \/ 3.4 x 2.4 x 1.5 in\u003c\/li\u003e\n\u003cli\u003eWeight: 64 g \/ 2.3 oz\u003c\/li\u003e\n\u003cli\u003eReplacement reagent set: HI783-25\u003c\/li\u003e\n\u003cli\u003eCalibration check set: HI783-11\u003c\/li\u003e\n\u003cli\u003eWarranty: 1 year manufacturer warranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eMarine Magnesium Testing Notes\u003c\/h3\u003e\n\u003cp\u003eFor best results, keep the prepared sample within Hanna’s required temperature range and use the supplied syringes as directed. Clean cuvettes carefully, avoid fingerprints and bubbles, and test consistently when adjusting magnesium, calcium, or alkalinity supplementation.\u003c\/p\u003e\n\u003ch3\u003eUsing the Hanna Magnesium Checker\u003c\/h3\u003e\n\u003cp\u003ePrepare the saltwater sample using the included syringes and HI783 reagents, insert the clean cuvette as directed, and read the magnesium value on the digital display. Replace reagents with Hanna HI783-25 when the included test supply is used up.\u003c\/p\u003e\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eHI783 Marine Magnesium Checker with protective case\u003c\/li\u003e\n\u003cli\u003eMarine magnesium reagent set for 25 tests\u003c\/li\u003e\n\u003cli\u003e2 glass cuvettes with caps\u003c\/li\u003e\n\u003cli\u003e5 mL syringe with tip and black printing\u003c\/li\u003e\n\u003cli\u003e5 mL syringe with tip and blue printing\u003c\/li\u003e\n\u003cli\u003e1.5V AAA alkaline battery\u003c\/li\u003e\n\u003cli\u003eInstruction manual\u003c\/li\u003e\n\u003cli\u003eQuick reference guide\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(255, 42, 0);\"\u003eALL SALES FINAL ON CLEARANCE ITEMS NO RETURNS, REFUNDS OR EXCHANGES.\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h4\u003e\n\u003c\/div\u003e","brand":"Hanna Instruments","offers":[{"title":"Default Title","offer_id":67888627646752,"sku":"HN-CKMAG-OP","price":59.39,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0951\/8222\/5696\/files\/magnesiumchecker_1_5a846800-da6f-4d3d-ae36-c84ad802d560.jpg?v=1792530410","url":"https:\/\/aquariumsupplydirect.com\/products\/hanna-magnesium-checker-open-box","provider":"J\u0026L Aquatics - Aquarium Supply Direct","version":"1.0","type":"link"}