I'm finding I'm in no way an expert, but I will tell you what has happened to state fishery ponds with salamanders.. 4 years ago 6 runs that had water over winter were stocked with FHM and 3 months later we found about the same amount of FHM remaining that were stocked with nearly 1000lbs of waterdogs total from the 6 runs. Seines were run through these about 1 week prior to stocking FHM and confirmed nothing present. Others more knowledgeable may say go ahead but I learned something from this that I would hate to see repeated. A few CC, 12-14" 5-8 per run are placed in right after runs are confirmed empty now.