{"product_id":"red-sea-magnesium-pro-reagent-refill-kit","title":"Red Sea Magnesium Pro Reagent Refill Kit","description":"\u003cp\u003e\u003cstrong\u003eA hundred more tests without a second titrator.\u003c\/strong\u003e This is the genuine Red Sea Magnesium Pro reagent refill, part R21416. It restocks the chemistry in the Magnesium Pro Test Kit (R21415) and restores the full 100 tests at Red Sea's stated 20 ppm resolution, while the titrator, dosing spoon, syringe, glass vials and case you already own stay exactly where they are.\u003c\/p\u003e\n\u003cp\u003eMagnesium is tested less often than alkalinity, so this bottle tends to run out on a longer clock — and to be the reagent most likely to have aged before it emptied.\u003c\/p\u003e\n\n\u003ch3\u003eKey features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eGenuine Red Sea part R21416\u003c\/strong\u003e — the same reagents supplied in the complete Magnesium Pro kit, not a third-party substitute.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRestores the full 100 tests\u003c\/strong\u003e — the same test count as a new kit, which is the largest in Red Sea's Pro foundation range.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e20 ppm resolution retained\u003c\/strong\u003e — fresh reagent is what that figure assumes; an aged bottle quietly stops delivering it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eKeeps the hardware\u003c\/strong\u003e — the titrator and dosing spoon are built to outlast many refills, so there is no reason to buy them twice.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFixes disagreeing kits\u003c\/strong\u003e — when two magnesium tests give different answers, the older reagent is almost always the one that is wrong.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat's included\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eRed Sea Magnesium Pro reagents, enough to restore 100 tests\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eNot included\u003c\/h3\u003e\n\u003cp\u003eThis is reagent only. The \u003cstrong\u003etitrator, dosing spoon, 5 mL syringe, glass vials, colour reference card, instruction manual and storage case\u003c\/strong\u003e all ship with the complete kit and are not repeated here.\u003c\/p\u003e\n\u003cp\u003eIf you do not already own the \u003ca href=\"\/products\/red-sea-magnesium-pro-testing-kit-100-tests\"\u003eRed Sea Magnesium Pro Test Kit\u003c\/a\u003e, buy the kit instead — on its own there is nothing in this box to titrate with, and no spoon to measure the powder step.\u003c\/p\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eManufacturer part number\u003c\/th\u003e\n\u003ctd\u003eR21416\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eRefill for\u003c\/th\u003e\n\u003ctd\u003eRed Sea Magnesium Pro Test Kit (R21415)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eParameter measured\u003c\/th\u003e\n\u003ctd\u003eMagnesium (Mg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTest method\u003c\/th\u003e\n\u003ctd\u003eTitration\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTests restored\u003c\/th\u003e\n\u003ctd\u003e100\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eResolution\u003c\/th\u003e\n\u003ctd\u003e20 ppm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSupplement metered\u003c\/th\u003e\n\u003ctd\u003eRed Sea Foundation C (Magnesium)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWater type\u003c\/th\u003e\n\u003ctd\u003eMarine and reef\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eStorage\u003c\/th\u003e\n\u003ctd\u003eOriginal containers, closed, cool and dry, away from acids, alkalis, oxidisers and metals\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eWill this fit my kit?\u003c\/h3\u003e\n\u003cp\u003eIt fits the Red Sea Magnesium Pro Test Kit, part R21415 — the titration kit with the single-hand titrator and the dosing spoon.\u003c\/p\u003e\n\u003cp\u003eIt does \u003cstrong\u003enot\u003c\/strong\u003e fit Red Sea's Marine Care magnesium test, which uses different chemistry, and it does not fit the magnesium test inside the \u003ca href=\"\/products\/red-sea-reef-foundation-pro-multi-testing-kit\"\u003eReef Foundation Pro Multi Test Kit\u003c\/a\u003e unless that kit's magnesium module is the Pro test. Check the reagent bottle labels against R21416 before ordering if you are unsure which kit you own.\u003c\/p\u003e\n\n\u003ch3\u003eCare and handling\u003c\/h3\u003e\n\u003cp\u003eLevel the dosing spoon every time. The powder step is measured by volume, and a heaped spoon moves the endpoint further than the 20 ppm the kit resolves to.\u003c\/p\u003e\n\u003cp\u003eRinse the vials in RO water between tests, and check salinity before you draw a sample — magnesium tracks with salinity, so a reading taken at the wrong specific gravity is misleading rather than merely imprecise.\u003c\/p\u003e\n\u003cp\u003eStore the reagents closed in their original containers, cool, dry and out of direct sun, away from acids, alkalis, oxidising compounds and metals. If a fresh refill reads differently from the bottle you were finishing, trust the fresh one.\u003c\/p\u003e\n\n\u003ch3\u003eSafety\u003c\/h3\u003e\n\u003cp\u003eRed Sea's safety data sheet covers this refill and the complete kit together, and gives Reagent A the signal word \u003cstrong\u003eDanger\u003c\/strong\u003e. Reagent A is classified as harmful if swallowed and harmful in contact with skin, causes severe skin burns and eye damage, and may be corrosive to metals. The named constituents are sodium tetraborate decahydrate at 1–5%, which carries a reproductive hazard classification, potassium hydroxide at 1–5% and oxalic acid at 1–5%. Reagents B and C carry no signal word.\u003c\/p\u003e\n\u003cp\u003eKeep out of reach of children. In the eyes, rinse with plenty of water for at least 15 minutes and get medical attention. If swallowed, do not induce vomiting — rinse the mouth thoroughly with water if the person is conscious, and get medical attention.\u003c\/p\u003e\n\n\u003ch3\u003eSuitable for, and not suitable for\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eSuitable for:\u003c\/strong\u003e anyone who already owns a Red Sea Magnesium Pro Test Kit and has run the reagents down or out of date.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eNot suitable for:\u003c\/strong\u003e a first purchase — there is no titrator, spoon or glassware in this box. It is also not for freshwater use, and it will not measure calcium or alkalinity.\u003c\/p\u003e\n\n\u003ch3\u003eGoes well with\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-magnesium-pro-testing-kit-100-tests\"\u003eRed Sea Magnesium Pro Testing Kit\u003c\/a\u003e — the kit this refill restocks, if you need the titrator too.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-reef-care-magnesium-foundation-c\"\u003eRed Sea Foundation C (Magnesium)\u003c\/a\u003e — the supplement you dose against the reading.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-alkalinity-pro-reagent-refill-kit\"\u003eRed Sea Alkalinity Pro Reagent Refill\u003c\/a\u003e — the reagent that empties fastest of the three.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-calcium-pro-reagent-refill-kit\"\u003eRed Sea Calcium Pro Reagent Refill\u003c\/a\u003e — the third foundation parameter.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-reef-care-reef-foundation-abc-3-pack-250ml-ea\"\u003eRed Sea Reef Foundation ABC 3 Pack\u003c\/a\u003e — all three supplements together.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/collections\/red-sea-1\"\u003eRed Sea range\u003c\/a\u003e — the rest of the Reef Care testing and supplement program.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWarranty and delivery\u003c\/h3\u003e\n\u003cp\u003eReagents are consumables and carry no service warranty. Any manufacturer warranty Red Sea offers applies in addition to your rights under the Australian Consumer Law, which are not limited or excluded by it.\u003c\/p\u003e\n\u003cp\u003eShips as a standard small parcel. The reagent volumes are well under the threshold for dangerous goods handling, so no special freight applies.\u003c\/p\u003e\n\n\u003ch3\u003eCommon questions\u003c\/h3\u003e\n\u003ch4\u003eHow many tests does the Red Sea Magnesium Pro reagent refill provide?\u003c\/h4\u003e\n\u003cp\u003eThe refill restores the Magnesium Pro Test Kit to its full 100-test count, which is the number of tests Red Sea specifies for the complete kit.\u003c\/p\u003e\n\u003ch4\u003eWhat is the Red Sea part number for this refill?\u003c\/h4\u003e\n\u003cp\u003eThe refill is Red Sea part R21416. The complete kit is R21415. Both are covered by the same Red Sea safety data sheet, because the refill supplies the same reagents.\u003c\/p\u003e\n\u003ch4\u003eDoes the refill include the titrator or the dosing spoon?\u003c\/h4\u003e\n\u003cp\u003eNo. The refill is reagent only. The titrator, dosing spoon, syringe, glass vials, colour card, manual and case all come with the complete Magnesium Pro Test Kit and are designed to be reused across many refills.\u003c\/p\u003e\n\u003ch4\u003eDo the reagents expire?\u003c\/h4\u003e\n\u003cp\u003eYes, and magnesium reagent is more likely than most to age out before it empties, because magnesium is typically tested fortnightly rather than several times a week. Check the date on the pack, and replace the reagent if a result stops agreeing with your other tests.\u003c\/p\u003e\n\u003ch4\u003eWill this refill work in Red Sea's Marine Care magnesium test?\u003c\/h4\u003e\n\u003cp\u003eNo. The Marine Care magnesium test uses different chemistry from the Pro titration kit, and the reagents are not interchangeable. This refill is specific to the Magnesium Pro Test Kit, part R21415.\u003c\/p\u003e","brand":"RedSea","offers":[{"title":"Default Title","offer_id":54774152233251,"sku":"RED252a","price":45.95,"currency_code":"AUD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0972\/7236\/5347\/files\/Red_Sea_Magnesium_Pro_Test_Refill.jpg?v=1782112634","url":"https:\/\/nicksaquariumoceanariumterrarium.com.au\/products\/red-sea-magnesium-pro-reagent-refill-kit","provider":"Nicks Aquarium Oceanarium Terrarium","version":"1.0","type":"link"}