I have two rain barrels setup and the lids have been on during times of no rain in hopes to keep mosquitoes from breeding in the water. However, I noticed today several hunderd larvea swimming around. Does anyone know of a way to kill off the mosquitoes but not kill the plants I use the water on? Right now I am using the water mainly for Sarracenia, Dionaea, and Drosera. I have also used it on occasion on my Nepenthes.