Hi looking for help my brother bought this house last year which included a pond it had fish and ducks on it and has been fine until a free weeks its stated looking dirty and now it's brown and horrible - it is large around 10 meter approx we have just found that it is fed from a gill on the fell behind its doesn't have any filter I don't think - my brother is away at the moment band I am taking care of the house ! Any idea would be a great help the trees on the fell behind him have been cut down in the past few years apart from that I don't know what has caused it