{"product_id":"quantum-aragonite-c-magnesium","title":"Quantum Aragonite C - Magnesium","description":"\u003cstyle\u003e\n  .aq-pd { font-family: Georgia, serif; color: #1a1a1a; max-width: 860px; margin: 0 auto; line-height: 1.7; }\n  .aq-pd h2 { font-size: 1.45em; font-weight: 700; letter-spacing: -0.01em; border-left: 4px solid #006064; padding-left: 12px; margin: 2em 0 0.6em; }\n  .aq-pd h3 { font-size: 1.05em; font-weight: 700; margin: 1.2em 0 0.4em; color: #006064; text-transform: uppercase; letter-spacing: 0.06em; font-family: Arial, sans-serif; }\n  .aq-pd p { margin: 0.5em 0 1em; }\n  .aq-callout { background: #003c3f; color: #fff; border-radius: 4px; padding: 16px 20px; margin: 1.6em 0; font-family: Arial, sans-serif; font-size: 0.93em; line-height: 1.6; }\n  .aq-callout strong { color: #A7FFEB; }\n  .aq-features { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 14px; margin: 1em 0 1.6em; }\n  .aq-feature-card { background: #E0F7FA; border-radius: 4px; padding: 14px 16px; border-left: 3px solid #006064; font-family: Arial, sans-serif; font-size: 0.9em; }\n  .aq-feature-card strong { display: block; margin-bottom: 3px; color: #1a1a1a; }\n  .aq-feature-card span { color: #555; }\n  .aq-compare { overflow-x: auto; margin: 1em 0 1.6em; }\n  .aq-compare table { width: 100%; border-collapse: collapse; font-family: Arial, sans-serif; font-size: 0.88em; min-width: 520px; }\n  .aq-compare th { background: #006064; color: #fff; padding: 9px 14px; text-align: center; font-weight: 700; letter-spacing: 0.05em; text-transform: uppercase; }\n  .aq-compare th:first-child { background: #003c3f; text-align: left; }\n  .aq-compare td { padding: 8px 14px; border-bottom: 1px solid #d0e8ea; text-align: center; }\n  .aq-compare td:first-child { text-align: left; font-weight: 600; color: #444; background: #f5fbfc; }\n  .aq-compare tr:nth-child(even) td:not(:first-child) { background: #f0fafb; }\n  .aq-specs-table { width: 100%; border-collapse: collapse; margin-top: 1em; font-family: Arial, sans-serif; font-size: 0.93em; }\n  .aq-specs-table th { background: #003c3f; color: #fff; text-align: left; padding: 9px 14px; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase; font-size: 0.82em; }\n  .aq-specs-table td { padding: 8px 14px; border-bottom: 1px solid #e5e5e5; vertical-align: top; }\n  .aq-specs-table tr:nth-child(even) td { background: #f7fcfd; }\n  .aq-specs-table td:first-child { font-weight: 600; width: 45%; color: #444; }\n  .aq-tab-radio { display: none; }\n  .aq-tab-labels { display: flex; flex-wrap: wrap; gap: 8px; margin: 1.4em 0 0; }\n  .aq-tab-label { display: inline-block; padding: 10px 22px; border: 2px solid #006064; background: #fff; color: #006064; font-weight: 700; font-family: Arial, sans-serif; font-size: 0.9em; cursor: pointer; border-radius: 3px; letter-spacing: 0.04em; transition: background 0.15s, color 0.15s; user-select: none; }\n  .aq-tab-label:hover { background: #B2EBF2; }\n  .aq-tab-panel { display: none; }\n  #aq-tab-250:checked ~ .aq-tab-labels label[for=\"aq-tab-250\"],\n  #aq-tab-500:checked ~ .aq-tab-labels label[for=\"aq-tab-500\"],\n  #aq-tab-1000:checked ~ .aq-tab-labels label[for=\"aq-tab-1000\"],\n  #aq-tab-5000:checked ~ .aq-tab-labels label[for=\"aq-tab-5000\"] { background: #006064; color: #fff; }\n  #aq-tab-250:checked ~ .aq-panels #aq-panel-250,\n  #aq-tab-500:checked ~ .aq-panels #aq-panel-500,\n  #aq-tab-1000:checked ~ .aq-panels #aq-panel-1000,\n  #aq-tab-5000:checked ~ .aq-panels #aq-panel-5000 { display: block; }\n  .aq-note { font-family: Arial, sans-serif; font-size: 0.82em; color: #777; margin-top: -0.5em; font-style: italic; }\n\u003c\/style\u003e\n\n\u003cdiv class=\"aq-pd\"\u003e\n\n  \u003cp\u003e\u003cstrong\u003eQuantum Aragonite C\u003c\/strong\u003e is a concentrated liquid magnesium supplement and the third part of Quantum's three part Aragonite reef dosing system. Magnesium is the quiet workhorse of reef chemistry: it keeps calcium and alkalinity in solution so they stay available to your corals instead of precipitating out. Get magnesium right and dosing the other two becomes easy. Pair it with \u003ca href=\"https:\/\/squeakysaquatics.com\/products\/quantum-aragonite-a-calcium\"\u003eAragonite A (Calcium)\u003c\/a\u003e and \u003ca href=\"https:\/\/squeakysaquatics.com\/products\/quantum-aragonite-b-alkalinity\"\u003eAragonite B (Alkalinity)\u003c\/a\u003e for complete, stable chemistry, and explore the rest of our \u003ca href=\"https:\/\/squeakysaquatics.com\/collections\/additives-supplements\"\u003ereef additives and supplements\u003c\/a\u003e.\u003c\/p\u003e\n\n  \u003cdiv class=\"aq-callout\"\u003e\n    \u003cstrong\u003eMagnesium is the foundation.\u003c\/strong\u003e If magnesium is low, calcium and alkalinity will not hold no matter how much you dose. Set magnesium first with Aragonite C, then balance \u003cstrong\u003eA and B\u003c\/strong\u003e on top of it. Magnesium is consumed slowly, so it usually needs only occasional topping up.\n  \u003c\/div\u003e\n\n  \u003ch2\u003eWhy Magnesium Matters\u003c\/h2\u003e\n  \u003cp\u003eMagnesium sits between calcium and carbonate in the water and stops them from binding together and falling out of solution. When magnesium runs low, you will see calcium and alkalinity drop together no matter how much you add. Aragonite C lets you hold magnesium in the ideal \u003cstrong\u003e1300 to 1350 ppm\u003c\/strong\u003e range, which is roughly three times your calcium level. With magnesium locked in, calcium (Aragonite A) and alkalinity (Aragonite B) stay stable and your corals get the steady chemistry they need.\u003c\/p\u003e\n\n  \u003ch2\u003eFeatures\u003c\/h2\u003e\n  \u003cdiv class=\"aq-features\"\u003e\n    \u003cdiv class=\"aq-feature-card\"\u003e\n\u003cstrong\u003eConcentrated Magnesium\u003c\/strong\u003e\u003cspan\u003eA strong magnesium source that goes a long way per dose.\u003c\/span\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"aq-feature-card\"\u003e\n\u003cstrong\u003eReef Safe Formula\u003c\/strong\u003e\u003cspan\u003eClean ingredients formulated specifically for marine and reef tanks.\u003c\/span\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"aq-feature-card\"\u003e\n\u003cstrong\u003ePart of a 3-Part System\u003c\/strong\u003e\u003cspan\u003eWorks hand in hand with Aragonite A (Calcium) and B (Alkalinity).\u003c\/span\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"aq-feature-card\"\u003e\n\u003cstrong\u003eHolds Cal and Alk Stable\u003c\/strong\u003e\u003cspan\u003eKeeps calcium and alkalinity in solution and available to corals.\u003c\/span\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"aq-feature-card\"\u003e\n\u003cstrong\u003eMade in Australia\u003c\/strong\u003e\u003cspan\u003eProduced by Quantum to a consistent, lab tested standard.\u003c\/span\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"aq-feature-card\"\u003e\n\u003cstrong\u003eFour Sizes\u003c\/strong\u003e\u003cspan\u003eFrom a 250 ml nano bottle to a 5 L jug for large or multiple reefs.\u003c\/span\u003e\n\u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003ch2\u003eChoose Your Size\u003c\/h2\u003e\n  \u003cp class=\"aq-note\"\u003eSelect a size in the tab section below for its full detail sheet.\u003c\/p\u003e\n  \u003cdiv class=\"aq-compare\"\u003e\n    \u003ctable\u003e\n      \u003cthead\u003e\n        \u003ctr\u003e\n          \u003cth\u003eSpec\u003c\/th\u003e\n          \u003cth\u003e250 ml\u003c\/th\u003e\n          \u003cth\u003e500 ml\u003c\/th\u003e\n          \u003cth\u003e1 L\u003c\/th\u003e\n          \u003cth\u003e5 L\u003c\/th\u003e\n        \u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003ctd\u003eVolume\u003c\/td\u003e\n\u003ctd\u003e250 ml\u003c\/td\u003e\n\u003ctd\u003e500 ml\u003c\/td\u003e\n\u003ctd\u003e1000 ml\u003c\/td\u003e\n\u003ctd\u003e5000 ml\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eBest For\u003c\/td\u003e\n\u003ctd\u003eNano \/ pico reefs\u003c\/td\u003e\n\u003ctd\u003eSmall reefs\u003c\/td\u003e\n\u003ctd\u003eMid size reefs\u003c\/td\u003e\n\u003ctd\u003eLarge or multiple reefs\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eValue per ml\u003c\/td\u003e\n\u003ctd\u003eGood\u003c\/td\u003e\n\u003ctd\u003eBetter\u003c\/td\u003e\n\u003ctd\u003eGreat\u003c\/td\u003e\n\u003ctd\u003eBest\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eAC250\u003c\/td\u003e\n\u003ctd\u003eAC500\u003c\/td\u003e\n\u003ctd\u003eAC1000\u003c\/td\u003e\n\u003ctd\u003eAC5000\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003ePrice\u003c\/td\u003e\n\u003ctd\u003e$22.49\u003c\/td\u003e\n\u003ctd\u003e$30.49\u003c\/td\u003e\n\u003ctd\u003e$44.99\u003c\/td\u003e\n\u003ctd\u003e$139.99\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n\n  \u003ch2\u003eDetailed Size Specifications\u003c\/h2\u003e\n  \u003cp\u003eClick a size below to view its full sheet.\u003c\/p\u003e\n\n  \u003cinput type=\"radio\" class=\"aq-tab-radio\" id=\"aq-tab-250\" name=\"aq-spec-tab\" checked\u003e\n  \u003cinput type=\"radio\" class=\"aq-tab-radio\" id=\"aq-tab-500\" name=\"aq-spec-tab\"\u003e\n  \u003cinput type=\"radio\" class=\"aq-tab-radio\" id=\"aq-tab-1000\" name=\"aq-spec-tab\"\u003e\n  \u003cinput type=\"radio\" class=\"aq-tab-radio\" id=\"aq-tab-5000\" name=\"aq-spec-tab\"\u003e\n\n  \u003cdiv class=\"aq-tab-labels\"\u003e\n    \u003clabel for=\"aq-tab-250\" class=\"aq-tab-label\"\u003e250 ml · Nano\u003c\/label\u003e\n    \u003clabel for=\"aq-tab-500\" class=\"aq-tab-label\"\u003e500 ml · Small\u003c\/label\u003e\n    \u003clabel for=\"aq-tab-1000\" class=\"aq-tab-label\"\u003e1 L · Mid\u003c\/label\u003e\n    \u003clabel for=\"aq-tab-5000\" class=\"aq-tab-label\"\u003e5 L · Large\u003c\/label\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"aq-panels\"\u003e\n    \u003cdiv class=\"aq-tab-panel\" id=\"aq-panel-250\"\u003e\n      \u003ch3\u003e250 ml · Nano \u0026amp; Pico Reefs\u003c\/h3\u003e\n      \u003cp\u003eThe starter bottle. Ideal for nano and pico reefs, or for trying the Aragonite system before stepping up to a larger jug.\u003c\/p\u003e\n      \u003ctable class=\"aq-specs-table\"\u003e\n        \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n        \u003ctbody\u003e\n          \u003ctr\u003e\n\u003ctd\u003eVolume\u003c\/td\u003e\n\u003ctd\u003e250 ml\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eAC250\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eRole\u003c\/td\u003e\n\u003ctd\u003eMagnesium (Part C)\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eBest For\u003c\/td\u003e\n\u003ctd\u003eNano and pico reef tanks\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003ePrice\u003c\/td\u003e\n\u003ctd\u003e$22.49\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003c\/tbody\u003e\n      \u003c\/table\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv class=\"aq-tab-panel\" id=\"aq-panel-500\"\u003e\n      \u003ch3\u003e500 ml · Small Reefs\u003c\/h3\u003e\n      \u003cp\u003eA practical everyday size for small reef systems keeping magnesium topped up.\u003c\/p\u003e\n      \u003ctable class=\"aq-specs-table\"\u003e\n        \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n        \u003ctbody\u003e\n          \u003ctr\u003e\n\u003ctd\u003eVolume\u003c\/td\u003e\n\u003ctd\u003e500 ml\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eAC500\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eRole\u003c\/td\u003e\n\u003ctd\u003eMagnesium (Part C)\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eBest For\u003c\/td\u003e\n\u003ctd\u003eSmall reef tanks\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003ePrice\u003c\/td\u003e\n\u003ctd\u003e$30.49\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003c\/tbody\u003e\n      \u003c\/table\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv class=\"aq-tab-panel\" id=\"aq-panel-1000\"\u003e\n      \u003ch3\u003e1 L · Mid Size Reefs\u003c\/h3\u003e\n      \u003cp\u003eThe best balance of value and shelf life for most established reef tanks.\u003c\/p\u003e\n      \u003ctable class=\"aq-specs-table\"\u003e\n        \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n        \u003ctbody\u003e\n          \u003ctr\u003e\n\u003ctd\u003eVolume\u003c\/td\u003e\n\u003ctd\u003e1000 ml (1 L)\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eAC1000\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eRole\u003c\/td\u003e\n\u003ctd\u003eMagnesium (Part C)\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eBest For\u003c\/td\u003e\n\u003ctd\u003eMid size reef tanks\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003ePrice\u003c\/td\u003e\n\u003ctd\u003e$44.99\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003c\/tbody\u003e\n      \u003c\/table\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv class=\"aq-tab-panel\" id=\"aq-panel-5000\"\u003e\n      \u003ch3\u003e5 L · Large or Multiple Reefs\u003c\/h3\u003e\n      \u003cp\u003eThe bulk jug for large, heavily stocked SPS systems or hobbyists running several reef tanks. The lowest cost per ml.\u003c\/p\u003e\n      \u003ctable class=\"aq-specs-table\"\u003e\n        \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n        \u003ctbody\u003e\n          \u003ctr\u003e\n\u003ctd\u003eVolume\u003c\/td\u003e\n\u003ctd\u003e5000 ml (5 L)\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eAC5000\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eRole\u003c\/td\u003e\n\u003ctd\u003eMagnesium (Part C)\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003eBest For\u003c\/td\u003e\n\u003ctd\u003eLarge or multiple reef tanks\u003c\/td\u003e\n\u003c\/tr\u003e\n          \u003ctr\u003e\n\u003ctd\u003ePrice\u003c\/td\u003e\n\u003ctd\u003e$139.99\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003c\/tbody\u003e\n      \u003c\/table\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003ch2\u003eWhich Size Is Right for You?\u003c\/h2\u003e\n  \u003cp\u003e\u003cstrong\u003e250 ml\u003c\/strong\u003e — Nano and pico reefs, or a low commitment way to start the Aragonite system.\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003e500 ml\u003c\/strong\u003e — Small reefs keeping magnesium in range.\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003e1 L\u003c\/strong\u003e — The sweet spot for most mid size reefs. Best mix of value and freshness.\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003e5 L\u003c\/strong\u003e — Large SPS systems or multiple tanks where you want the lowest cost per ml.\u003c\/p\u003e\n\n  \u003ch2\u003eHow to Dose\u003c\/h2\u003e\n  \u003cp\u003eAlways test before you dose. Use a quality magnesium test kit, then add Aragonite C to bring magnesium into the \u003cstrong\u003e1300 to 1350 ppm\u003c\/strong\u003e range. Magnesium is used up slowly, so once you reach your target you usually only need to top it up occasionally rather than daily. Follow the dosing guide on the bottle and adjust to your own test results. Keep calcium, alkalinity, and magnesium in balance by dosing \u003ca href=\"https:\/\/squeakysaquatics.com\/products\/quantum-aragonite-a-calcium\"\u003eAragonite A\u003c\/a\u003e, \u003ca href=\"https:\/\/squeakysaquatics.com\/products\/quantum-aragonite-b-alkalinity\"\u003eB\u003c\/a\u003e, and C together, and pick up a reliable kit from our \u003ca href=\"https:\/\/squeakysaquatics.com\/collections\/water-testing\"\u003ewater testing\u003c\/a\u003e collection.\u003c\/p\u003e\n\n  \u003ch2\u003eFAQ\u003c\/h2\u003e\n  \u003cp\u003e\u003cstrong\u003eWhy can I not keep my calcium and alkalinity up?\u003c\/strong\u003e\u003cbr\u003eLow magnesium is the usual culprit. When magnesium is below range, calcium and carbonate bind and precipitate, so they fall no matter how much you dose. Set magnesium with Aragonite C first.\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003eWhat magnesium level should I aim for?\u003c\/strong\u003e\u003cbr\u003eMost reef keepers hold 1300 to 1350 ppm, roughly three times the calcium level. Test, then dose Aragonite C to reach that range.\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003eHow often do I dose magnesium?\u003c\/strong\u003e\u003cbr\u003eLess often than calcium or alkalinity. Magnesium is consumed slowly, so after you set it you usually just top up occasionally based on testing.\u003c\/p\u003e\n  \u003cp\u003e\u003cstrong\u003eDo I need all three Aragonite products?\u003c\/strong\u003e\u003cbr\u003eYes. Calcium, alkalinity, and magnesium work as a set. Magnesium is the foundation that lets \u003ca href=\"https:\/\/squeakysaquatics.com\/products\/quantum-aragonite-a-calcium\"\u003ecalcium\u003c\/a\u003e and \u003ca href=\"https:\/\/squeakysaquatics.com\/products\/quantum-aragonite-b-alkalinity\"\u003ealkalinity\u003c\/a\u003e stay where you want them.\u003c\/p\u003e\n\n\u003c\/div\u003e","brand":"Quantum USA","offers":[{"title":"250 ml","offer_id":48837726077147,"sku":"AC250","price":22.49,"currency_code":"USD","in_stock":true},{"title":"500 ml","offer_id":48837726109915,"sku":"AC500","price":30.49,"currency_code":"USD","in_stock":true},{"title":"1000 ml (1 L)","offer_id":48837726142683,"sku":"AC1000","price":44.99,"currency_code":"USD","in_stock":true},{"title":"5000 ml (5 L)","offer_id":48837726175451,"sku":"AC5000","price":139.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0767\/5209\/3403\/files\/image_6015b13f-e905-4d93-afa1-55242fe6ab80.png?v=1780498409","url":"https:\/\/squeakysaquatics.com\/products\/quantum-aragonite-c-magnesium","provider":"Squeaky's Aquatics","version":"1.0","type":"link"}