{"product_id":"red-sea-foundation-c-magnesium-powder-1kg-reef-supplement","title":"Red Sea Foundation C Magnesium Powder 1 KG (2.2lb)","description":"\u003ch3 style=\"margin:14px 0 4px;font-size:1.05em;font-weight:600;line-height:1.25;border-left:4px solid #006064;padding-left:8px;\"\u003eMagnesium supplement for balanced formation of coral skeleton\u003c\/h3\u003e\n\n\u003cp\u003e\u003cstrong\u003eIt's all in the balance.\u003c\/strong\u003e Calcium, Magnesium, Strontium, and Carbonate are the basic foundation elements of coral skeletons. All of these elements need to be available in balanced proportions for positive coral growth — and Magnesium is the one most reefers forget until corals stop growing.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eRed Sea Foundation C\u003c\/strong\u003e is a concentrated magnesium powder (Mg + minor and trace elements) designed to be dosed alongside Foundation A (Calcium) and Foundation B (Alkalinity) to maintain natural seawater ionic balance in any reef tank. Browse the full \u003ca href=\"https:\/\/squeakysaquatics.com\/collections\/additives-supplements\"\u003ereef additives\u003c\/a\u003e and \u003ca href=\"https:\/\/squeakysaquatics.com\/collections\/salt-water\"\u003esaltwater supplies\u003c\/a\u003e lineup.\u003c\/p\u003e\n\n\u003ch3 style=\"margin:14px 0 4px;font-size:1.05em;font-weight:600;line-height:1.25;border-left:4px solid #006064;padding-left:8px;\"\u003eWhy Magnesium Matters\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStops calcium\/alkalinity precipitation\u003c\/strong\u003e — at low Mg levels, Ca and Alk react and crash. Holding Mg at ~1300 ppm keeps the foundation elements stable.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRequired for coralline growth\u003c\/strong\u003e — coralline algae uses magnesium for its skeleton just like SPS corals do.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTrace blend included\u003c\/strong\u003e — Foundation C is more than just MgCl₂; it includes minor and trace elements found in natural seawater.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePairs with A \u0026amp; B\u003c\/strong\u003e — completes the Red Sea Foundation Program (A=Ca, B=Alk, C=Mg).\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3 style=\"margin:14px 0 4px;font-size:1.05em;font-weight:600;line-height:1.25;border-left:4px solid #006064;padding-left:8px;\"\u003eHow to Use\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest first\u003c\/strong\u003e — measure your current Mg with a reliable reef test kit. Target: 1280–1340 ppm. Don't dose blindly.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDissolve in RO\/DI water\u003c\/strong\u003e — mix 1 KG of Foundation C into roughly 5 L of RO\/DI water (per Red Sea instructions; refer to the label for exact dosing per ppm raise).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDose slowly\u003c\/strong\u003e — never raise Mg by more than ~100 ppm per day. Sudden swings stress corals.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaintain with regular testing\u003c\/strong\u003e — recheck weekly. SPS-heavy tanks typically need ongoing Mg dosing as corals deplete the supply.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3 style=\"margin:14px 0 4px;font-size:1.05em;font-weight:600;line-height:1.25;border-left:4px solid #006064;padding-left:8px;\"\u003eSpecifications\u003c\/h3\u003e\n\u003ctable style=\"width:100%;border-collapse:collapse;margin:6px 0 10px;\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;width:42%;\"\u003e\u003cstrong\u003eBrand\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003eRed Sea\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003e\u003cstrong\u003eProduct\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003eReef Foundation C (Magnesium)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003e\u003cstrong\u003eSize\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003e1 KG (2.2 lb)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003e\u003cstrong\u003eForm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003eConcentrated powder (dissolve in RO\/DI)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003e\u003cstrong\u003eUse\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003eReef aquariums — magnesium maintenance \u0026amp; correction\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003e\u003cstrong\u003eTarget Mg\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003e1280–1340 ppm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003e\u003cstrong\u003ePairs With\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #B2EBF2;padding:6px 10px;\"\u003eFoundation A (Ca), Foundation B (Alk)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3 style=\"margin:14px 0 4px;font-size:1.05em;font-weight:600;line-height:1.25;border-left:4px solid #006064;padding-left:8px;\"\u003eThe Red Sea Foundation Program\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/squeakysaquatics.com\/products\/red-sea-reef-foundation-a-calcium-powder-1kg\"\u003eFoundation A — Calcium Powder 1 KG\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/squeakysaquatics.com\/products\/red-sea-reef-foundation-b-alkalinity-powder-1kg\"\u003eFoundation B — Alkalinity Powder 1 KG\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFoundation C — Magnesium Powder 1 KG\u003c\/strong\u003e (this product)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/squeakysaquatics.com\/products\/red-sea-reef-foundation-pro-multi-test-kit-ca-alk-mg\"\u003eFoundation Pro Multi Test Kit (Ca, Alk, Mg)\u003c\/a\u003e — test all three with one kit\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3 style=\"margin:14px 0 4px;font-size:1.05em;font-weight:600;line-height:1.25;border-left:4px solid #006064;padding-left:8px;\"\u003eRecommended Pairings\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/squeakysaquatics.com\/products\/aquaforest-af-magnesium-test-kit-saltwater-reef\"\u003eAquaforest AF Magnesium Test Kit\u003c\/a\u003e — alternative Mg test\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/squeakysaquatics.com\/collections\/water-testing\"\u003eAll water testing kits\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/squeakysaquatics.com\/collections\/additives-supplements\"\u003eAll aquarium additives \u0026amp; supplements\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/squeakysaquatics.com\/collections\/salt-mixes\"\u003eSalt mixes\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3 style=\"margin:14px 0 4px;font-size:1.05em;font-weight:600;line-height:1.25;border-left:4px solid #006064;padding-left:8px;\"\u003eFAQ\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eHow much does 1 KG raise Mg?\u003c\/strong\u003e\u003cbr\u003e\nA 1 KG bag dissolved in 5 L of RO\/DI water yields a concentrated stock solution. Refer to the label for exact dose-per-ppm-raise calculations based on your tank volume. As a rough rule, the bag will treat hundreds of gallons of tank water over time.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I dose this dry?\u003c\/strong\u003e\u003cbr\u003e\nNo — always dissolve in RO\/DI water first. Dosing the powder directly can crash local water chemistry and stress nearby corals.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow often should I test Mg?\u003c\/strong\u003e\u003cbr\u003e\nWeekly is standard for established reef tanks. Test more often if you've recently corrected a low Mg reading or added significant SPS coral.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs it reef safe?\u003c\/strong\u003e\u003cbr\u003e\nYes — Foundation C is formulated specifically for marine reef aquariums when dosed at the recommended rate.\u003c\/p\u003e","brand":"Red Sea","offers":[{"title":"Default Title","offer_id":48784859693275,"sku":"R22037","price":33.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0767\/5209\/3403\/files\/image_9653f8e9-8383-4611-872f-6e633ed5d906.jpg?v=1779135747","url":"https:\/\/squeakysaquatics.com\/products\/red-sea-foundation-c-magnesium-powder-1kg-reef-supplement","provider":"Squeaky's Aquatics","version":"1.0","type":"link"}