I build a new pond this summer and added all new plants. I had an infestation of beige coloured creatures the size of a pin head at most which multiplied into thousands and happily munched on all my plants especially the water lilly. I changed the water completly and cleaned it, replantsed with mainly new plants and they have come back. Does anyone know what they are and how to deal with them. Establishing anything is becoming a real problem, any help would really be appreciated.