i have about a 100 gallon pond in my backyard and every time i put anacharis and hornwort , they just brown out and die. the pond is about 1 year old. I've tried over the summer through winter, is it getting to much sun? it gets sunlight when the sun comes up to when the sun goes down. i have some water hardy lilies im waiting to plant when the water gets warmer, anyone know how to keep pond plants from dying? i live in southern california, zone 8b i think.