I had a pond with acquired through buying an existing house with garden about 2x2m and approx 1.4m deep. Water quality was well modest, ie heavily clouded by algae. Filter system was in with, but ran only sporadically and, although in a filter pot holder was in it, without UV lamp. So ordered and installed lamp and filter longer active. After about 1.5 weeks significantly improved water quality in some cases really clear to the bottom. Unfortunately enough, with a daily operating time of 12 hours, the service life for only one season. Well with what a pond otherwise costs per year (eg new plant) is ok.
