{"product_id":"red-sea-no3-po4-x-500ml","title":"Red Sea NO3:PO4-X 500ml","description":"\u003cp\u003e\u003cstrong\u003eOne capful a day starves nuisance algae without starving your fish.\u003c\/strong\u003e Red Sea NO3:PO4-X is a liquid carbon source that feeds the bacteria already living in your reef system, encouraging them to consume excess nitrate and phosphate straight out of the water column. This 500 mL bottle is the size to start with — enough to run a full conversion in a small-to-medium reef, or to confirm the product suits your tank before stepping up to the 1 L or 5 L size.\u003c\/p\u003e\n\n\u003ch3\u003eKey features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeeds your own bacteria\u003c\/strong\u003e — a blend of carbon sources, each favoured by a different naturally occurring bacterial strain, so nutrient reduction happens biologically rather than through media that needs replacing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTreats nitrate and phosphate together\u003c\/strong\u003e — one bottle addresses both nutrients that drive nuisance algae, instead of running separate products for each.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDosed by an exact chart, not guesswork\u003c\/strong\u003e — Red Sea publishes a daily dose in millilitres per 100 L, set by your current nitrate and phosphate reading.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnder 1c per litre of tank water treated\u003c\/strong\u003e — even at Red Sea's top dosing rate, this 500 mL bottle works out to well under a cent for every litre it treats.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRoom-temperature storage\u003c\/strong\u003e — no refrigeration required; keep out of direct light.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpec\u003c\/th\u003e\n\u003cth\u003eRed Sea NO3:PO4-X 500 mL\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\u003eForm\u003c\/td\u003e\n\u003ctd\u003eLiquid concentrate, dosed daily\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWater type\u003c\/td\u003e\n\u003ctd\u003eMarine \/ reef\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLitres treated at the conservative dosing rate\u003c\/td\u003e\n\u003ctd\u003eApprox. 16,650 L over the life of the bottle\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCost per litre of water treated\u003c\/td\u003e\n\u003ctd\u003eUnder 1c per litre\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eDosing chart — Red Sea's published rates\u003c\/h3\u003e\n\u003cp\u003eDose is set by your current nitrate and phosphate readings, not a flat daily amount. Test weekly while dosing and adjust as levels fall.\u003c\/p\u003e\n\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eParameter\u003c\/th\u003e\n\u003cth\u003eCurrent level\u003c\/th\u003e\n\u003cth\u003eDaily dose\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003ePhosphate (PO₄)\u003c\/td\u003e\n\u003ctd\u003eBelow 0.04 ppm\u003c\/td\u003e\n\u003ctd\u003e1 mL per 100 L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePhosphate (PO₄)\u003c\/td\u003e\n\u003ctd\u003e0.04–0.2 ppm\u003c\/td\u003e\n\u003ctd\u003e2 mL per 100 L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePhosphate (PO₄)\u003c\/td\u003e\n\u003ctd\u003eAbove 0.2 ppm\u003c\/td\u003e\n\u003ctd\u003e3 mL per 100 L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNitrate (NO₃)\u003c\/td\u003e\n\u003ctd\u003eBelow 1 ppm\u003c\/td\u003e\n\u003ctd\u003e1 mL per 100 L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNitrate (NO₃)\u003c\/td\u003e\n\u003ctd\u003eAbove 1 ppm\u003c\/td\u003e\n\u003ctd\u003e2 mL per 100 L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eWhere both nutrients are elevated at once, follow Red Sea's full instructions on combining the two doses rather than simply adding them together.\u003c\/p\u003e\n\n\u003ch3\u003eCost per litre — which size to buy\u003c\/h3\u003e\n\u003cp\u003eAll three NO3:PO4-X sizes work out to under 1 cent per litre of tank water treated at Red Sea's top dosing rate, but the larger bottles stretch further per dollar. The 500 mL bottle is the right starting size if you're new to carbon dosing or run a smaller system.\u003c\/p\u003e\n\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSize\u003c\/th\u003e\n\u003cth\u003ePrice\u003c\/th\u003e\n\u003cth\u003eApprox. litres treated*\u003c\/th\u003e\n\u003cth\u003eCost per litre\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e500 mL (this bottle)\u003c\/td\u003e\n\u003ctd\u003e$27.00\u003c\/td\u003e\n\u003ctd\u003e~16,650 L\u003c\/td\u003e\n\u003ctd\u003eUnder 1c per litre\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1 L\u003c\/td\u003e\n\u003ctd\u003e$42.00\u003c\/td\u003e\n\u003ctd\u003e~33,300 L\u003c\/td\u003e\n\u003ctd\u003eUnder 1c per litre\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e5 L\u003c\/td\u003e\n\u003ctd\u003e$157.00\u003c\/td\u003e\n\u003ctd\u003e~166,650 L\u003c\/td\u003e\n\u003ctd\u003eUnder 1c per litre\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e*Calculated at Red Sea's top published dosing rate of 3 mL per 100 L per day — the conservative, lowest-yield case, used when phosphate reads above 0.2 ppm. At lower nutrient levels the same bottle treats considerably more water and lasts longer.\u003c\/p\u003e\n\n\u003ch3\u003eSuitable for, and not suitable for\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eSuitable for established marine and reef aquariums running an efficient protein skimmer.\u003c\/li\u003e\n\u003cli\u003eSuitable for use alongside Red Sea's Algae Management program when converting a tank off phosphate- and nitrate-absorbing media.\u003c\/li\u003e\n\u003cli\u003eNot suitable for use at the same time as sulphur-based denitrators.\u003c\/li\u003e\n\u003cli\u003eNot a spot treatment — this product doses the whole system daily, not a single application.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eDosage and directions\u003c\/h3\u003e\n\u003cp\u003eAdd daily to the sump, or to a high-flow area of the display if there's no sump — never dosed directly onto coral. If this is your first time carbon dosing, start at half the recommended rate for the first few days and watch skimmer output, which will increase as bacteria multiply. A dosing pump keeps the small daily volume consistent.\u003c\/p\u003e\n\n\u003ch3\u003eCare and maintenance\u003c\/h3\u003e\n\u003cp\u003eTest nitrate and phosphate weekly while dosing and adjust to the chart above. Keep the protein skimmer running efficiently — the bacteria this product feeds are exported largely through skimmate, so a \u003ca href=\"\/products\/red-sea-reefer-skimmer-300-psk600\"\u003eskimmer sized to your system\u003c\/a\u003e matters as much as the dose itself.\u003c\/p\u003e\n\n\u003ch3\u003eSafety\u003c\/h3\u003e\n\u003cp\u003eReduce the dose by half if nitrate falls below 0.25 ppm, and don't increase the dose faster than the chart allows — overdosing a carbon source can crash dissolved oxygen. Red Sea recommends switching off any UV steriliser while dosing, since UV will kill the bacteria the product is feeding. Not for use in planted or shrimp-only systems.\u003c\/p\u003e\n\n\u003ch3\u003eGoes well with\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-nutrients-control-multi-test-kit-no3-po4\"\u003eRed Sea Nutrients Control Multi Test Kit (NO3\/PO4)\u003c\/a\u003e — the weekly nitrate and phosphate test this dosing chart is based on.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-reefer-skimmer-300-psk600\"\u003eRed Sea Reefer Skimmer 300\u003c\/a\u003e — efficient skimming is what exports the nutrient-laden bacteria this product feeds.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWarranty and delivery\u003c\/h3\u003e\n\u003cp\u003eBacked by Red Sea's standard product warranty, in addition to your rights under Australian Consumer Law. A 500 mL bottle ships as a standard parcel.\u003c\/p\u003e\n\n\u003ch3\u003eCommon questions\u003c\/h3\u003e\n\u003ch4\u003eIs NO3:PO4-X reef safe?\u003c\/h4\u003e\n\u003cp\u003eYes, when dosed according to the chart above. Overdosing any carbon source can affect dissolved oxygen, so start conservatively and increase gradually while watching your skimmer.\u003c\/p\u003e\n\u003ch4\u003eHow long will a 500 mL bottle last?\u003c\/h4\u003e\n\u003cp\u003eAt Red Sea's top dosing rate it treats roughly 16,650 L of tank water — for a 200 L system dosed daily at the highest rate, that's a little over four months. Most tanks use less than the top rate, so a bottle typically lasts longer.\u003c\/p\u003e\n\u003ch4\u003eCan I use NO3:PO4-X alongside GFO or nitrate-removing media?\u003c\/h4\u003e\n\u003cp\u003eYes — Red Sea's Algae Management program is built around gradually removing absorption media while introducing this product. Follow Red Sea's published conversion schedule rather than removing media all at once.\u003c\/p\u003e\n\u003ch4\u003eDo I need a UV steriliser switched off?\u003c\/h4\u003e\n\u003cp\u003eRed Sea recommends turning off a UV steriliser while dosing, since it will kill the bacteria this product relies on to reduce nitrate and phosphate.\u003c\/p\u003e","brand":"RedSea","offers":[{"title":"Default","offer_id":55269637095715,"sku":null,"price":27.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0972\/7236\/5347\/files\/Red_Sea_NO3PO4-X_eece9613-dab0-423b-8403-cb7418e4ab32.jpg?v=1782107395","url":"https:\/\/nicksaquariumoceanariumterrarium.com.au\/products\/red-sea-no3-po4-x-500ml","provider":"Nicks Aquarium Oceanarium Terrarium","version":"1.0","type":"link"}