I can't answer that as I never used it in my trout pond.
I've always thought that darker stained water warmed up faster, but I believe Bill Cody once said it's the reverse with the dye.
Bill?
Your thought makes sense to me, Cecil - it would seem logical that the darker water color would absorb heat energy more readily, just like wearing dark colored clothing on a sunny day versus light colored clothing. I'll be interested in Bill's response as I've not read anything by him about that before.