So I'd like to collect some of the native aquatics around me, but I worry. Virtually every natural body of freshwater around here is a creek or a bog fed by a creek, and they all have an orange slime. It seems to grow out of the sand and collect at the edges, on plant stems, basically anything it can stick to. It's especially prevalent in slower flows or still waters.
I don't know if it's a bacteria, a fungus, or a kind of algae but it eventually chokes anything submerged.
It might be colonies of the same iron-munching bacteria that sporadically pop up in our residential well, necessitating chlorine shock treatments once or twice a year. Our soil here is mostly rust-rich Piedmont red clay, chemically weathered from the underlying iron-filled and calcium-poor bedrock.
Whatever it is, it's unsightly and kills plants so I'd like to keep it off of anything I happen to collect. I brought in some Hydrocotyle verticillata cuttings a few weeks ago and plopped them into a shallow container with pre-boiled water, a bit of calcium chicken grit, and some oven-sterilized soils. Now the orange scum is evident in the water and forming a mat around the submerged portion of the cuttings and their shoots, and the leaves are starting to turn yellow and wilt away. It didn't come in through the water or the soil, so I'm thinking it probably hitched a ride on the untreated plants.
What's the recommended method of killing unwanted scums on wild-caught plants anymore? Is it still potassium permanganate or hydrogen peroxide solution?