Hello Richard. I've always topped up my pond with rainwater from the waterbutt. But we still get blanket weed. We have 2 newts, still very small and very shy. We had lots of tad and toadpoles, but I think the birds eat a lot of them. They certainly eat the pondskaters,as we saw a blackbird with several in his beak. The water is getting rather murky and on sunny days you can almost see the blanket weed grow !! We have decided to try (am I allowed to mention a product?) Aquaplancton. Not cheap, but all the reviews are very positive. Enjoy all the recolonisation in your pond. It's fascinating, isn't it? By the way, we don't have any fish, only natural wildlife.