When gardening using hydroponic methods you will often find yourself using large quantities of nutrient solution, especially if you’re growing more than a couple of plants. This means you’ll probably be buying large bottles of nutrients to save money and a big 20 litre bottle means it can be hard to be accurate with your application thanks to the weight of the solution.
By using a plastic funnel you can reduce spillages and potential harm to yourself or your plants. Some nutrients or additives can be mild irritants or harmful to the skin, they could also damage your plants if they were spilled on to them undiluted. Not to mention you don’t have to worry about wasting a single drop!