I'm landscaping the area around my pond and I'm not sure what kind of mulch to use. I know not to use rubber because it can be too hot for the frogs. I was planning on using double shredded natural mulch because there is no dye in it however when I am done mulching a customer (I have a small landscape business) my hands are still stained brown from the natural mulch. I'm worried about the rain water running off of the mulch and into the pond and making the water brown. Could this happen?