{"product_id":"red-sea-reef-care-4-part-rcp-medium-300ltr","title":"Red Sea Reef Care 4 Part RCP Medium 300ltr","description":"\u003cp\u003e\u003cstrong\u003eA single dosing programme keeps calcium, alkalinity, magnesium and coral trace elements in step for a 300 L reef.\u003c\/strong\u003e The Red Sea 4-Part RCP — Medium pack — bottles the same four-part programme as the rest of the RCP range, proportioned to run a mixed reef up to 300 L for roughly three months.\u003c\/p\u003e\u003ch3\u003eKey features\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSized for reefs to 300 L\u003c\/strong\u003e — built around roughly three months of daily dosing for a mixed reef at that volume.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFour parts, one ratio\u003c\/strong\u003e — Part 1 (Calcium \u0026amp; Magnesium+), Part 2 (Alkalinity\/KH \u0026amp; pH stabiliser), Part 3 (Iodine \u0026amp; Potassium) and Part 4 (Iron \u0026amp; Bioactive Elements), bottled so all four run out together.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e36 major, minor and trace elements\u003c\/strong\u003e in the ratio found in coral skeleton and tissue.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManual or automated dosing\u003c\/strong\u003e — works by hand or through a Red Sea ReefDose.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSet your dose from testing\u003c\/strong\u003e, using a Red Sea Reef Foundation test kit, rather than the label rate alone.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpec\u003c\/th\u003e\n\u003cth\u003eDetail\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eRED877\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarcode\u003c\/td\u003e\n\u003ctd\u003e7290116399041\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReef volume\u003c\/td\u003e\n\u003ctd\u003eUp to 300 L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApprox. duration\u003c\/td\u003e\n\u003ctd\u003e~3 months, mixed reef, dosed to programme\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eParts included\u003c\/td\u003e\n\u003ctd\u003e4 — Ca\/Mg, Alkalinity, Iodine\/Potassium, Iron\/Bioactive Elements\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWater type\u003c\/td\u003e\n\u003ctd\u003eSaltwater (reef)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDosing method\u003c\/td\u003e\n\u003ctd\u003eManual or Red Sea ReefDose 4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eWhich size do I need?\u003c\/h3\u003e\u003cp\u003eAll three RCP packs dose the same four elements in the same ratio — they differ only in reef volume and cost per 100 L over the roughly three-month cycle.\u003c\/p\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003ePack\u003c\/th\u003e\n\u003cth\u003eReef volume\u003c\/th\u003e\n\u003cth\u003eApprox. cost per 100 L, per 3-month cycle\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eSmall\u003c\/td\u003e\n\u003ctd\u003eUp to 160 L\u003c\/td\u003e\n\u003ctd\u003e$68.13\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMedium\u003c\/td\u003e\n\u003ctd\u003eUp to 300 L\u003c\/td\u003e\n\u003ctd\u003e$63.00\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLarge\u003c\/td\u003e\n\u003ctd\u003eUp to 600 L\u003c\/td\u003e\n\u003ctd\u003e$49.83\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cp\u003eFor a 300 L reef dosed at the mixed-reef guide rate (~3 mL per 100 L per day), that's about 9 mL of each part daily — the Medium pack is sized so all four bottles last roughly three months at that rate.\u003c\/p\u003e\u003ch3\u003eDosing and elemental targets\u003c\/h3\u003e\u003cp\u003eFoundation elements (Parts 1 and 2) are formulated so 1 mL per 100 L raises calcium by 2 ppm, magnesium by roughly 1 ppm, and alkalinity by about 0.034 dKH — but the right daily dose is whatever your reef is actually consuming, not the label maximum.\u003c\/p\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eReef type\u003c\/th\u003e\n\u003cth\u003eTypical daily dose\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eMixed reef\u003c\/td\u003e\n\u003ctd\u003e~3 mL per 100 L, each part\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSPS-dominant\u003c\/td\u003e\n\u003ctd\u003e~4 mL per 100 L, each part\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSPS frag \/ high growth\u003c\/td\u003e\n\u003ctd\u003e~6 mL per 100 L, each part\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUltra-low-nutrient system\u003c\/td\u003e\n\u003ctd\u003e~2 mL per 100 L, each part\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cp\u003eNever exceed a daily increase of 20 ppm calcium, 0.5 meq\/L (1.4 dKH) alkalinity or 10 ppm magnesium — spread any larger correction over several days. When dosing manually, add magnesium first, then alkalinity, then calcium, with about 10 minutes between each. Part 4 (Iron \u0026amp; Bioactive Elements) has no single target ppm — Red Sea's guidance is to dose it in proportion to how much of Parts 1–3 your reef is using.\u003c\/p\u003e\u003ch3\u003eWhat's included \/ Not included\u003c\/h3\u003e\u003cp\u003eIncluded: four dosing solutions — Calcium \u0026amp; Magnesium+, Alkalinity\/KH \u0026amp; pH Stabiliser, Iodine \u0026amp; Potassium, and Iron \u0026amp; Bioactive Elements — proportioned for a 300 L reef over roughly three months.\u003c\/p\u003e\u003cp\u003eNot included: dosing pump, test kits, and the calcium\/alkalinity\/magnesium test results you'll need to set your own daily dose accurately. A Red Sea Reef Foundation test kit and either manual dosing or a ReefDose unit are what you'll still need to run the programme properly.\u003c\/p\u003e\u003ch3\u003eSuitable for, and not suitable for\u003c\/h3\u003e\u003cp\u003eSuitable for an established 150–300 L saltwater reef running coral, where calcium, alkalinity and magnesium need topping up against consumption.\u003c\/p\u003e\u003cp\u003eNot suitable for fish-only or newly cycled tanks with no coral demand — dosing without a measurable uptake risks pushing parameters too high. Not a substitute for water changes, and not intended for freshwater systems.\u003c\/p\u003e\u003ch3\u003eWarranty and delivery\u003c\/h3\u003e\u003cp\u003eCovered by the standard manufacturer guarantee against faulty product, in addition to your rights under Australian Consumer Law. Liquid reef additives ship as standard parcel freight from Brisbane; no special handling required for this pack size.\u003c\/p\u003e\u003ch3\u003eCommon questions\u003c\/h3\u003e\u003ch4\u003eDo I need a test kit to use this?\u003c\/h4\u003e\u003cp\u003eYou can dose to the tank-type guide above as a starting point, but Red Sea's own instructions recommend testing calcium, alkalinity and magnesium regularly and adjusting the dose to what your reef is actually using — dosing blind risks over- or under-shooting.\u003c\/p\u003e\u003ch4\u003eWhat's the difference between the Small, Medium and Large packs?\u003c\/h4\u003e\u003cp\u003eThe same four elements in the same ratio — only the bottle sizes and the reef volume they're built for change. See the size comparison table above.\u003c\/p\u003e\u003ch4\u003eCan I dose all four parts at once?\u003c\/h4\u003e\u003cp\u003eRed Sea recommends spacing magnesium, alkalinity and calcium about 10 minutes apart when dosing manually, to avoid a local spike that can precipitate elements out of solution. The trace element part (Part 4) isn't time-sensitive in the same way.\u003c\/p\u003e\u003ch4\u003eCould I use the Large pack instead, to save on reorders?\u003c\/h4\u003e\u003cp\u003eYes — the Large pack (up to 600 L) works fine on a 300 L reef; you'd just be dosing roughly half the bottle per day, so it lasts closer to six months instead of three, at a lower cost per 100 L. It's a larger upfront cost for the same total elements.\u003c\/p\u003e\u003ch4\u003eWhat happens if I miss a few days of dosing?\u003c\/h4\u003e\u003cp\u003eCorals will draw down calcium, alkalinity and magnesium from the water in the meantime. Test before resuming and dose to the measured deficit rather than doubling up the next day's dose, which risks a large swing.\u003c\/p\u003e","brand":"RedSea","offers":[{"title":"Default Title","offer_id":54774162456867,"sku":"RED877","price":189.0,"currency_code":"AUD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0972\/7236\/5347\/files\/Red-Sea-Complete-Reef-Care.png?v=1782112702","url":"https:\/\/nicksaquariumoceanariumterrarium.com.au\/products\/red-sea-reef-care-4-part-rcp-medium-300ltr","provider":"Nicks Aquarium Oceanarium Terrarium","version":"1.0","type":"link"}