{"product_id":"hanna-hi781-marine-nitrate-low-range-colorimeter-reef-aquarium","title":"Hanna Instruments HI781 Marine Nitrate Low Range Colorimeter for Reef \u0026 Saltwater Aquariums","description":"\u003ch2\u003eHanna Instruments HI781 Marine Nitrate Low Range Colorimeter\u003c\/h2\u003e\u003cp\u003eProtect your reef and saltwater aquarium with pinpoint nitrate accuracy. The \u003cstrong\u003eHanna Instruments HI781 Checker® HC\u003c\/strong\u003e is a handheld colorimeter engineered to measure low-range nitrate levels from \u003cstrong\u003e0.00 to 5.00 ppm (as NO3–)\u003c\/strong\u003e — far more reliably than color-matching test kits. No more squinting at color charts; get a clear digital readout every time.\u003c\/p\u003e\u003ch3\u003eWhy Nitrate Control Matters in Reef Aquariums\u003c\/h3\u003e\u003cp\u003eNitrate is a natural by-product of the nitrogen cycle. Too much promotes algae blooms and dinoflagellate outbreaks; too little starves SPS corals, causing color loss and tissue recession. The HI781 gives you the precise data you need to keep your reef thriving.\u003c\/p\u003e\u003ch3\u003eKey Features\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMeasurement range:\u003c\/strong\u003e 0.00–5.00 ppm NO3– (extend to 0–50 ppm with the approved dilution procedure).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDigital readout\u003c\/strong\u003e — eliminates visual color-matching errors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt-in timer\u003c\/strong\u003e — guides you through each step so you never miss a reaction window.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSaltwater-optimized\u003c\/strong\u003e — calibrated specifically for marine and reef aquarium water chemistry.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMore accurate than test kits\u003c\/strong\u003e — uses the Beer-Lambert colorimetric principle for lab-grade results.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSingle-parameter dedicated\u003c\/strong\u003e — no cross-interference from other parameters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompact \u0026amp; portable\u003c\/strong\u003e — handheld design fits easily in your aquarium toolkit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIdeal for:\u003c\/strong\u003e reef aquariums, marine biology, and professional saltwater applications.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eHow It Works\u003c\/h3\u003e\u003cp\u003eAdd the pre-measured HI781-25 reagent packet to your water sample. The HI781 uses the Beer-Lambert principle to detect the pink\/violet color change caused by the nitrate-reagent reaction and converts it to a precise ppm reading — in minutes.\u003c\/p\u003e\u003ch3\u003eIn the Box\u003c\/h3\u003e\u003cp\u003eHI781 Checker® HC colorimeter, sample cuvettes, HI781-25 reagent sachets (starter supply), instructions. Replacement reagents sold separately as \u003cstrong\u003eHI781-25 (25 tests)\u003c\/strong\u003e.\u003c\/p\u003e","brand":"HANNA Instruments","offers":[{"title":"Default Title","offer_id":41991258538071,"sku":"HI781","price":74.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1555\/0581\/files\/HI781-Front__67689.jpg?v=1758677062","url":"https:\/\/getultimatenow.com\/products\/hanna-hi781-marine-nitrate-low-range-colorimeter-reef-aquarium","provider":"Get Ultimate Now ","version":"1.0","type":"link"}