Limb Bream,
Speaking as a windshield (
), yes it is far better to prevent a problem from ever happening than to try to recover from one.
GC are a good example of that. If you have read other posts herein and/or talked to fish pros, you will generally be exposed to the wait 'till you have a problem and then stock 10 to 15 GC per acre.
I've had neighbors follow that advice and they end up with a pond full of hungry fat GC, no vegetation for fish protection/rearing, muddy water, and basically no easy way to get rid of the GC.
This is what I have found to be effective...stock two per acre before the problem happens and rotate them out every three years with young replacements. In a 1/3 acre pond, I would start with only one GC and watch what happens. If you see weeds begin to grow/expand add another one (but I doubt you will need to), if not just sit tight and replace it in three years. One other tidbit of experience with GC, they love to escape through a spillway or flowing water. To prevent this, you need to have a fish gate in place at points where water exits your pond.
The GC is very useful for vegetation control and when used in low numbers to prevent/control weeds are a great tool for the pond meister.
