RR - I respect BGK's adverse experience with GC - and if you overstock them they certainly can become a problem. If they overeat their forage base they will resort to rooting for invertabrates in the pond bottom as their primary/preferred forage source has been exhausted - causing turbidity. However, I know GC can be an effective vegetation management device as it's currently working on my main pond. The critical factor is determining the appropriate stocking quantity. I've seen some hatcheries recommend 8-10 GC/acre. I feel this is way high - start low - allow 2-3 years - and reassess. 3-5/surface acre is the highest I would recommend.

Your stocking of 30 GC on a 10 acre bow is within that range and I feel you'll see some favorable results in a couple years. I can't imagine the cost of chemically treating 10 acres of water, anyhow.

If you notice your vegetation disappearing, the result will be excess nutrients and will result in either excessive FA or thick algae blooms. At this time I'd recommend beginning to target your GC for removal - and while I haven't had the opportunity to try this, it appears a difficult but not impossible task.

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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