I have a small (UK) plastic pond that was doing very well on its own for a few years, we just cleared out the leaves as needed. The year before last the water went dark and murky and I added products to help clear it which didn’t work. Later on we realised the lily in there had well outgrown its pot and the root ball had taken over 2/3rds of the pond so obviously was choking the pond up so we removed it totally and all the sludge that was left behind and cleaned the plastic liner. We refilled it with tap water that we had let stand around outside in buckets for a few days but it kept turning green quickly once put into the pond. We added a small oxygenating plant which didn’t thrive at all, some product to help clear the green away and later a new lily which also seemed to die off quickly but it continued to go green and murky. Life has got in the way and the pond is now awful, filled with leaves and all brown. We can’t devote a lot of time to reviving it but we’re also loathe to lose it as we do love the wildlife it attracts. I mean it’s really small but still brings joy. What should we now to do recover it? We think we’ll have to completely empty it and start again. What plants / products will help get it back on track? Thank you.