{"product_id":"red-sea-kh-alkalinity-pro-testing-kit-75-tests","title":"Red Sea KH\/Alkalinity Pro Testing Kit 75 Tests","description":"\u003cp\u003e\u003cstrong\u003eAlkalinity read to 0.14 dKH, not guessed off a colour card.\u003c\/strong\u003e The Red Sea KH\/Alkalinity Pro Test Kit is a 75-test titration kit that measures carbonate alkalinity (KH, your tank's pH buffer) to a resolution of 0.05 meq\/L, which is 0.14 dKH. It arrives with the single-hand titrator, 68 mL of titrant, a 10 mL syringe and a 100 mL sample of Foundation B, so the first correction can be made the day it lands.\u003c\/p\u003e\n\u003cp\u003eAlkalinity is the parameter a stocked reef consumes fastest, and the one corals punish you soonest for letting swing. A kit that resolves to a seventh of a dKH shows you a drift while it is still a drift.\u003c\/p\u003e\n\n\u003ch3\u003eKey features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTitration, not colour matching\u003c\/strong\u003e — you read a number off a syringe scale instead of holding a vial against a printed card under kitchen lighting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e0.05 meq\/L (0.14 dKH) resolution\u003c\/strong\u003e — fine enough to separate a real trend from test-to-test noise, which a 1 dKH colour kit cannot do.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e75 tests per kit\u003c\/strong\u003e — about nine months of twice-weekly testing on a single reef.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSingle-hand titrator\u003c\/strong\u003e — one hand works the plunger while the other swirls the vial, which is the difference between a repeatable endpoint and a rushed one.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e100 mL Foundation B sample included\u003c\/strong\u003e — the buffer this kit exists to meter, enough to make your first correction before you commit to a full bottle.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReagent refills available\u003c\/strong\u003e — the titrator, syringe, vial and case are designed to outlast many bottles of titrant.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat's in the box\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eSingle-hand high-precision titrator\u003c\/li\u003e\n\u003cli\u003eTitrant, 68 mL — enough for 75 tests\u003c\/li\u003e\n\u003cli\u003e10 mL syringe\u003c\/li\u003e\n\u003cli\u003eAnalytical-grade glass vial\u003c\/li\u003e\n\u003cli\u003eColour reference card\u003c\/li\u003e\n\u003cli\u003eInstruction manual\u003c\/li\u003e\n\u003cli\u003e100 mL sample of Red Sea Foundation B (KH\/Alkalinity)\u003c\/li\u003e\n\u003cli\u003eChemical-resistant plastic storage case\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eNot included\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eA full-size bottle of buffer. The 100 mL Foundation B sample is a starter, not a supply — \u003ca href=\"\/products\/red-sea-reef-care-kh-foundation-b\"\u003eRed Sea Foundation B\u003c\/a\u003e is sold separately.\u003c\/li\u003e\n\u003cli\u003eCalcium and magnesium tests. Those are the \u003ca href=\"\/products\/red-sea-calcium-pro-testing-kit-75-tests\"\u003eCalcium Pro\u003c\/a\u003e and \u003ca href=\"\/products\/red-sea-magnesium-pro-testing-kit-100-tests\"\u003eMagnesium Pro\u003c\/a\u003e kits, or all three together in the \u003ca href=\"\/products\/red-sea-reef-foundation-pro-multi-testing-kit\"\u003eReef Foundation Pro Multi Test Kit\u003c\/a\u003e.\u003c\/li\u003e\n\u003cli\u003eA refractometer or salinity meter. Salinity has to be correct before an alkalinity result means anything.\u003c\/li\u003e\n\u003c\/ul\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\u003eR21410\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eParameter measured\u003c\/th\u003e\n\u003ctd\u003eCarbonate alkalinity (KH, the tank's pH buffer)\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\u003eNumber of tests\u003c\/th\u003e\n\u003ctd\u003e75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eResolution\u003c\/th\u003e\n\u003ctd\u003e0.05 meq\/L (0.14 dKH)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMeasuring range\u003c\/th\u003e\n\u003ctd\u003eNot fixed — a titration reads to its endpoint rather than off a printed scale\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTitrant supplied\u003c\/th\u003e\n\u003ctd\u003e68 mL\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSample syringe\u003c\/th\u003e\n\u003ctd\u003e10 mL\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSupplement metered\u003c\/th\u003e\n\u003ctd\u003eRed Sea Foundation B (KH\/Alkalinity)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eReagent refill\u003c\/th\u003e\n\u003ctd\u003eRed Sea part R21411\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, out of direct sunlight\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eWhat alkalinity should I be running?\u003c\/h3\u003e\n\u003cp\u003eThere is no single correct figure. Red Sea publishes foundation targets by system type in its Foundation Supplements manual, and alkalinity only makes sense read alongside the calcium and magnesium it is balanced against.\u003c\/p\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eSystem\u003c\/th\u003e\n\u003cth\u003eAlkalinity\u003c\/th\u003e\n\u003cth\u003eCalcium\u003c\/th\u003e\n\u003cth\u003eMagnesium\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMixed reef\u003c\/th\u003e\n\u003ctd\u003e11.5 dKH (4.1 meq\/L)\u003c\/td\u003e\n\u003ctd\u003e450 mg\/L\u003c\/td\u003e\n\u003ctd\u003e1350 mg\/L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSPS dominant\u003c\/th\u003e\n\u003ctd\u003e8.0 dKH (2.9 meq\/L)\u003c\/td\u003e\n\u003ctd\u003e430 mg\/L\u003c\/td\u003e\n\u003ctd\u003e1280 mg\/L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMarine fish only\u003c\/th\u003e\n\u003ctd\u003e6.8 dKH (2.4 meq\/L)\u003c\/td\u003e\n\u003ctd\u003e370 mg\/L\u003c\/td\u003e\n\u003ctd\u003e1100 mg\/L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eRed Sea's wider Reef Care guidance spans roughly 7 to 12 dKH, trading growth rate against coloration. Pick a target, hold it, and move it slowly if you change your mind. Stability beats the number.\u003c\/p\u003e\n\n\u003ch3\u003eWhat to do when the reading is off\u003c\/h3\u003e\n\u003ch4\u003eBelow your target\u003c\/h4\u003e\n\u003cp\u003eDose \u003ca href=\"\/products\/red-sea-reef-care-kh-foundation-b\"\u003eRed Sea Foundation B\u003c\/a\u003e, the buffer this kit meters. Red Sea states a maximum safe increase of 1.4 dKH (0.5 meq\/L) in a single day — going faster stresses corals rather than helping them.\u003c\/p\u003e\n\u003ch4\u003eAbove your target\u003c\/h4\u003e\n\u003cp\u003eStop dosing and let consumption bring it down, or dilute it with a water change. Do not chase alkalinity downwards with acid.\u003c\/p\u003e\n\u003ch4\u003eDrifting when nothing has changed\u003c\/h4\u003e\n\u003cp\u003eCalcium, alkalinity and magnesium move as a set. A stubborn alkalinity reading is usually low magnesium, so test all three before adjusting any of them.\u003c\/p\u003e\n\n\u003ch3\u003eWhich Red Sea alkalinity test do I need?\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eKit\u003c\/th\u003e\n\u003cth\u003eResolution\u003c\/th\u003e\n\u003cth\u003eChoose it when\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eKH\/Alkalinity Pro (this kit)\u003c\/th\u003e\n\u003ctd\u003e0.14 dKH\u003c\/td\u003e\n\u003ctd\u003eYou keep corals and dose a buffer, so small movements matter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMarine Care alkalinity test\u003c\/th\u003e\n\u003ctd\u003e1 dKH (0.36 meq\/L)\u003c\/td\u003e\n\u003ctd\u003eFish-only or a maturing system, where a whole dKH is close enough\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003ca href=\"\/products\/red-sea-reef-foundation-pro-multi-testing-kit\"\u003eReef Foundation Pro Multi\u003c\/a\u003e\u003c\/th\u003e\n\u003ctd\u003eSame Pro chemistry\u003c\/td\u003e\n\u003ctd\u003eYou want calcium, alkalinity and magnesium in one case\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCare and storage\u003c\/h3\u003e\n\u003cp\u003eCorrect salinity before you test. An alkalinity reading taken at the wrong specific gravity is measuring the wrong water.\u003c\/p\u003e\n\u003cp\u003eRinse the glass vial in RO water between tests. Leftover titrant is one of the two things that quietly bias a result; the other is reagent age.\u003c\/p\u003e\n\u003cp\u003eStore the titrant closed, in its original container, in the kit's case, cool and dry and out of direct sun. If a fresh bottle of titrant reads noticeably differently from the one 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 for this kit and its refill carries the signal word \u003cstrong\u003eWarning\u003c\/strong\u003e. The titrant is listed as monoethylene glycol (an antifreeze-type solvent) at 50–75%, harmful if swallowed, and hydrochloric acid at under 1%, which can cause severe skin and eye burns and may irritate the airways.\u003c\/p\u003e\n\u003cp\u003eKeep it out of reach of children and away from acids, alkalis, oxidisers and metals. 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 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 reef aquariums of any size where corals are consuming alkalinity, anyone dosing a two- or three-part supplement and needing to meter it, and anyone whose colour-card kit reads the same before and after a dose.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eNot suitable for:\u003c\/strong\u003e freshwater KH testing, where a low-cost colour kit is entirely adequate and this resolution is wasted. It also will not tell you calcium or magnesium, and it is not a replacement for a salinity check.\u003c\/p\u003e\n\n\u003ch3\u003eGoes well with\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-alkalinity-pro-reagent-refill-kit\"\u003eRed Sea Alkalinity Pro Reagent Refill\u003c\/a\u003e — part R21411, restores all 75 tests without rebuying the titrator.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-reef-care-kh-foundation-b\"\u003eRed Sea Foundation B (KH\/Alkalinity)\u003c\/a\u003e — the full-size buffer you dose against the reading.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-magnesium-pro-testing-kit-100-tests\"\u003eRed Sea Magnesium Pro Test Kit\u003c\/a\u003e — the parameter that explains most stubborn alkalinity readings.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/red-sea-calcium-pro-testing-kit-75-tests\"\u003eRed Sea Calcium Pro Test Kit\u003c\/a\u003e — the third of the foundation trio.\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 — salts, supplements and the rest of the Reef Care 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. A kit arriving with leaking, damaged or out-of-date reagents is replaced.\u003c\/p\u003e\n\u003cp\u003eShips as a standard 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 accurate is the Red Sea KH\/Alkalinity Pro Test Kit?\u003c\/h4\u003e\n\u003cp\u003eRed Sea specifies a resolution of 0.05 meq\/L, which is 0.14 dKH. Because it is a titration rather than a colour comparison, the measurement is not bounded by a printed scale — you titrate to an endpoint and read the volume used.\u003c\/p\u003e\n\u003ch4\u003eHow many tests are in the kit, and what does a refill cost me?\u003c\/h4\u003e\n\u003cp\u003eThe kit contains 68 mL of titrant, enough for 75 tests. The reagent refill is Red Sea part R21411 and restores the full 75-test count, so you only ever buy the titrator, syringe, vial and case once.\u003c\/p\u003e\n\u003ch4\u003eDoes the kit include the alkalinity supplement?\u003c\/h4\u003e\n\u003cp\u003eIt includes a 100 mL sample of Red Sea Foundation B, which is enough to make an initial correction but is not an ongoing supply. A full-size bottle of Foundation B is bought separately.\u003c\/p\u003e\n\u003ch4\u003eCan I use this kit on a freshwater aquarium?\u003c\/h4\u003e\n\u003cp\u003eThe chemistry will measure carbonate hardness in fresh water, but the kit is built around the resolution a reef needs. For a freshwater or planted tank a standard colour-comparison KH kit is cheaper and perfectly adequate.\u003c\/p\u003e\n\u003ch4\u003eMy alkalinity keeps falling no matter how much buffer I dose. What is wrong?\u003c\/h4\u003e\n\u003cp\u003eTest magnesium. Magnesium holds calcium and alkalinity in solution, and when it runs low both of the others become impossible to hold no matter how much you dose. Correct magnesium first, then re-test alkalinity.\u003c\/p\u003e\n\u003ch4\u003eHow often should I test alkalinity?\u003c\/h4\u003e\n\u003cp\u003eRed Sea's Reef Care approach is built on regular testing rather than a fixed interval, and most reefers with a stocked coral load test two or three times a week. On a new or heavily stocked system, test more often until the daily consumption rate is known.\u003c\/p\u003e","brand":"RedSea","offers":[{"title":"Default Title","offer_id":54774152134947,"sku":"RED251","price":60.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0972\/7236\/5347\/files\/RED251_2.png?v=1772078658","url":"https:\/\/nicksaquariumoceanariumterrarium.com.au\/products\/red-sea-kh-alkalinity-pro-testing-kit-75-tests","provider":"Nicks AOT","version":"1.0","type":"link"}