GC are selective which you've learned - and coincidentally sucks since per Eric AMPW is considered a beneficial species vs. coontail and happens to be a preferred forage. The risk you may now be facing, despite your best intentions with biological management with GC stocking, is monoculture of coontail. Initially at least you have AMPW competing with the coontail...sorry to be a bummer. Consider removing your GC and hope the AMPW grows back is an option.

I have coontail present in all 7 of my ponds - started in one, got transferred by [I'm assuming Canada Geese and/or ducks] to the other ponds. There's nothing I figure I can do but pray my beneficial species continue to compete with the coontail. If I hit with fluridone I'm going to nuke all my beneficial species along with the coontail - leading to major nutrient loads and potenital water quality issues to deal with. I've successfully spot treated coontail in the past with Aquathol Super K granules which worked great, but it's expensive and IMO a useless exercise as the coontail just kept coming back in other areas.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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