Hi, We had a new patio put down about 4 months ago, It is indian sandstone. We were told to put down a sealer but also told not to. At the moment parts of it have turned green and I have used jeyes fluid and the hose to clear it partially. What I would like to know is if anyone else used a product to clear the green stains and also if anyone could reccomend a good sealer as I think I should use one now as soon as I have it back to its original standard, Thanks in advance, Salaried.