{"product_id":"aqua-master-p50-pro2-ph-meter-waterproof-ph-temperature-pen","title":"Aqua Master P50 Pro2 pH Meter - Waterproof pH \u0026 Temperature Pen","description":"\u003ch2\u003eStop Guessing Your Feed pH with the Aqua Master P50 Pro2 pH Meter\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003eAqua Master P50 Pro2\u003c\/strong\u003e is a waterproof pH pen that reads pH and temperature in your reservoir, nutrient tank or watering can, accurate to \u003cstrong\u003e±0.1 pH\u003c\/strong\u003e. It calibrates itself, corrects for temperature, runs on two AAA batteries and floats if it ends up in the tank.\u003c\/p\u003e\n\u003ch3\u003eWhy You Need It\u003c\/h3\u003e\n\u003cp\u003epH decides whether your plants can use the feed you've paid for. Hydro and coco feeds typically run at pH 5.5 to 6.5. Drift outside that and nutrients lock out at the roots, so the plant goes hungry in a tank full of food. And because nutrients shift pH the moment they hit the water, you need to check every mix.\u003c\/p\u003e\n\u003ch3\u003eIs the P50 Pro2 Right for Your Setup?\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFirst pH meter:\u003c\/strong\u003e automatic calibration and a 30-day reminder leave very little to get wrong.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNeed EC too?\u003c\/strong\u003e This pen doesn't measure feed strength. Add the \u003ca href=\"https:\/\/www.onestopgrowshop.co.uk\/products\/aqua-master-e50-pro-ec-temperature-meter\"\u003eAqua Master E50 EC Meter\u003c\/a\u003e, or get both in one with the \u003ca href=\"https:\/\/www.onestopgrowshop.co.uk\/products\/aqua-master-p100-pro-ec-ph-temp-combo-pen\"\u003eP110 Combo Pen\u003c\/a\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTesting straight into coco or soil?\u003c\/strong\u003e It reads liquids, not media. Call us and we'll point you to a substrate meter.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eHow the P50 Pro2 Works\u003c\/h3\u003e\n\u003cp\u003eThe glass bulb at the tip reads how acidic the solution is, and a built-in sensor applies ATC (automatic temperature compensation, which corrects for water temperature) from 0 to 50°C. You can show 0.1 or 0.01 pH. The second decimal helps you spot drift, but accuracy stays ±0.1 pH, so don't chase the hundredths.\u003c\/p\u003e\n\u003ch3\u003eKey Benefits\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eIP67 waterproof:\u003c\/strong\u003e it floats, so a slip into the reservoir is a fish-out, not a funeral.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSelf-calibrating:\u003c\/strong\u003e it recognises pH 7.00 and 4.01 buffer and sets itself.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e30-day reminder:\u003c\/strong\u003e the CAL tick disappears when it's due again.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAAA batteries:\u003c\/strong\u003e no hunting for button cells, plus a low battery warning.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReplaceable electrode:\u003c\/strong\u003e swap the tip when it wears out, not the whole meter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAuto power-off:\u003c\/strong\u003e shuts down after 8 minutes if you forget.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eContains\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1 x P50 Pro2 meter with protective cap and cap cord\u003c\/li\u003e\n\u003cli\u003e2 x 1.5V AAA batteries and user manual\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eNot included: \u003ca href=\"https:\/\/www.onestopgrowshop.co.uk\/products\/aqua-master-calibration-solutions-100ml\"\u003epH 4 and pH 7 calibration solutions\u003c\/a\u003e and \u003ca href=\"https:\/\/www.onestopgrowshop.co.uk\/products\/growth-technology-ph-probe-refill-storage-solution-300ml\"\u003eKCl storage solution\u003c\/a\u003e.\u003c\/p\u003e\n\u003ch3\u003eP50 Pro2 Specifications\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003epH range\u003c\/th\u003e\n\u003ctd\u003e0.0 to 14.0 pH\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003epH accuracy\u003c\/th\u003e\n\u003ctd\u003e±0.1 pH\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003epH resolution\u003c\/th\u003e\n\u003ctd\u003e0.1 or 0.01 pH\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eTemperature\u003c\/th\u003e\n\u003ctd\u003e0 to 50°C, ±1°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eCalibration\u003c\/th\u003e\n\u003ctd\u003eAutomatic 2-point, pH 7.00 and 4.01\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eWaterproof rating\u003c\/th\u003e\n\u003ctd\u003eIP67, floats\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003ePower\u003c\/th\u003e\n\u003ctd\u003e2 x 1.5V AAA, included\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eSize and weight\u003c\/th\u003e\n\u003ctd\u003e230 x 43 x 43mm, 132g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eWarranty\u003c\/th\u003e\n\u003ctd\u003e1 year meter, 6 months electrode\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eHow To Use the P50 Pro2\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eSoak it:\u003c\/strong\u003e before first use, stand the electrode in tap water for at least 12 hours.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCalibrate:\u003c\/strong\u003e dip in pH 7.00 buffer at 25°C, wait for a steady reading and hold CAL for 5 seconds. Rinse and repeat with pH 4.01.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMix your feed:\u003c\/strong\u003e set your EC first, because nutrients move pH.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest and adjust:\u003c\/strong\u003e dip the pen upright, stir gently, then add pH up or down a little at a time until you're in range.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStore it wet:\u003c\/strong\u003e rinse, add a few drops of KCl storage solution to the cap and stand it upright.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003cstrong\u003eTop tip:\u003c\/strong\u003e More pH pens die from bad storage than faults. Never leave the electrode dry or in RO, distilled or deionised water. Pure water strips the reference liquid inside and your readings go wandering.\u003c\/p\u003e\n\u003ch3\u003eFAQs\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eWhat's the difference between the P50 Pro and P50 Pro2?\u003c\/strong\u003e\u003cbr\u003eThe Pro2 adds AAA batteries, a white-on-black display, the 0.01 pH option and the 30-day reminder. It takes the same replacement electrode as the Pro.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eThere's white crust on the electrode. Is it faulty?\u003c\/strong\u003e\u003cbr\u003eNo. Dried salts on a new electrode are normal, and the 12-hour soak dissolves them.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhy does my reading keep jumping?\u003c\/strong\u003e\u003cbr\u003eUsually air bubbles, low batteries or electrical interference. Stir gently, change the batteries and test away from ballasts and other electrical kit.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eNeed help choosing?\u003c\/strong\u003e Call our growing experts on 01782 749955 or visit One Stop Grow Shop Stoke at Fenton Trade Park.\u003c\/p\u003e\n\u003cp\u003eGet pH right and every bottle of feed works harder. \u003ca href=\"https:\/\/www.onestopgrowshop.co.uk\/collections\/grow-tools-slash-accessories-meters\"\u003eBrowse our full range of pH and EC meters\u003c\/a\u003e.\u003c\/p\u003e","brand":"AQUA MASTER","offers":[{"title":"Default Title","offer_id":57511523287418,"sku":null,"price":53.99,"currency_code":"GBP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0762\/6368\/6447\/files\/aquamasterp50pr2phmeter.jpg?v=1793877429","url":"https:\/\/www.onestopgrowshop.co.uk\/products\/aqua-master-p50-pro2-ph-meter-waterproof-ph-temperature-pen","provider":"One Stop Grow Shop","version":"1.0","type":"link"}