One site happens to be a floating sphagnum bog in Orange County, New York, near Port Jervis, and has
D. rotundifolia and
D. intermedia (pictured with some Lycopodium sp.) as well as
S. purpurea, pictured with the flowering Utrics.
D. intermedia gets very large in some places, even bushy! The water here is slightly acidic, the first site has no sphagnum, and tests neutral (pH=7.0) and has a lot of clay in the detritus, even some clay basin pools where tubiflex worms grow in large mats just under the strands.
Aldovanda will feed on mosquito larvae, small snails, copepods, small shrimp, and even small fish, and other creatures of the zooplankton community, anything that will fit into its traps; btw, Aldrovanda are the ONLY aquatic CP that can catch and digest all stages of mosquito larvae, even the largest ones; Utrics can only handel the smaller stages.
I can't really recomend water lilies, as their leaves occupy too much water surface, and prevent the Aldrovanda strands from recieving direct sunlight. In this site, the Aldrovanda nearly gets choked to death by them at the end of summer! The same with Salvinea, water hyacinths, and water lettuce and other aquatic plants that cover the surface area of the water.
As for chemicals, one site is a rainwater drainage basin in back of a shopping mall, and gets tons of calcium chloride as well as sodium chloride and other salts during the winter snow and ice storms, even oil slicks and who knows what!? Yet they seem to grow well as long as they have their symbiotic friends with them, and enough rain to wash out the harmful things!
- Rich