{"product_id":"4mm-airline-check-valve","title":"4mm Airline Check Valve – Non-Return Valve (Packs of 2 or 5)","description":"\u003ch2\u003e4mm Airline Check Valve – Cheap Insurance for Your Air Pump\u003c\/h2\u003e\n\u003cp\u003eHere's a scenario nobody thinks about until it happens: the power cuts out overnight, the air pump stops, and with nothing pushing air down the line, water quietly siphons back up the airline and into the pump. Best case, a puddle. Worst case, a dead pump. A check valve stops it. It's a one-way valve that lets air flow down to the stone but blocks water from ever coming back.\u003c\/p\u003e\n\u003ch3\u003eWhen You Need One\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eYour air pump sits \u003cstrong\u003elevel with or below\u003c\/strong\u003e the water line\u003c\/li\u003e\n\u003cli\u003eYou run air into \u003cstrong\u003ereservoirs, DWC buckets, semi-hydro or ponds\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eYou'd rather not find out the hard way\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eHow to Fit\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003eCut the airline between the pump and the air stone.\u003c\/li\u003e\n\u003cli\u003ePush the valve into the gap with its \u003cstrong\u003earrow pointing towards the air stone\u003c\/strong\u003e, away from the pump.\u003c\/li\u003e\n\u003cli\u003eFit one valve in each airline.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003eIf no air reaches the stone after fitting, the valve is in backwards. Simply flip it round.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e🌿 Rose's Pro-Tip:\u003c\/strong\u003e fit the valve close to the pump rather than near the water. It keeps the valve dry and lets it seal properly.\u003c\/p\u003e\n\u003cp\u003eFits all standard 4mm airline, pumps and air stones.\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003eBlack Flag Horticulture Ltd, Coventry.\u003c\/em\u003e\u003c\/p\u003e","brand":"HydroGarden","offers":[{"title":"Pack of 2","offer_id":55105909031258,"sku":"BFH-CHECKVALVE-4MM-2","price":2.99,"currency_code":"GBP","in_stock":true},{"title":"Pack of 5","offer_id":55105909064026,"sku":"BFH-CHECKVALVE-4MM-5","price":5.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0774\/9861\/4106\/files\/SnWucuVH.jpg?v=1793447909","url":"https:\/\/blackflaghorticulture.com\/sq\/products\/4mm-airline-check-valve","provider":"Black Flag Horticulture","version":"1.0","type":"link"}