With the constant water coming through it, minerals will build up on the rain showerhead, which can restrict the flow and eventually clog it. A great solution is to buy one of these showerheads, which have soft rubber tips as these can be wiped off to remove the likes of calcium and lime. If you do have a build-up, then there is an easy way to solve it without using dangerous chemicals. White vinegar is highly effective at breaking down mineral deposits. All you need to do is soak the product for 15-20 minutes and then give it a rinse.