This iron sulphate is really easy to use , and is good value . The only thing that could make it better is if it came with a measuring spoon . The instructions state 2grams per litre of water but how do you measure 2 grams without a set of digital scales ? If they had included a small plastic measuring spoon inside the container for the right amount of granules for 5 litres of water (10 grams) it would have made life a lot easier . In the event it was fine because I just went back on e bay and ordered a low cost set of electronic cooking scales that can measure from 1gram upwards . They only cost around £6 free delivery on E Bay 👍⭐️⭐️⭐️⭐️⭐️