Straight from the desk of Deb's fish farm (hee-hee)...
I have yet to have a hands on experience with the fathead minnow, but the gambusia has far exceeded the expectations of every customer of ours that has stocked them. Even our dealer in Muncie, Indiana has great success with both raising and selling gambusia. They are quick swimmers, prolific breeders, and are rather intelligent in my opinion. I say intelligent for several reasons. Any half brained fish can wander dumbfounded into open water, but the gambs appear to exhibit a higher fish IQ (funny thought) than the fatheads I have read about. Not only do they attempt to avoid predation, but they often are successful at it for awhile.
As far as the cost per lb issue I see it like this. 500 female gambusia giving live birth every 28 days or so during spawning season would be equal to or even cheaper than stocking 500 fatheads who do not survive to see a spawn. A little drastic I know... but you all are intelligent enough fish to see my point.
Which fish is REALLY cheaper to stock in the long run? If you have to add fatheads every month or two... we must look at the entire forest (long term) and not just one pretty and cheap tree (short term).
I personally have yet to see harm from stocking the gambs. Quite the contrary I have seen tremendous results when stocked with the GG and other bream (also the HSB).
Speaking as a mother who gave live birth versus laying an egg out in open water(or attached to some structure making for easy prey)... heck I just have to really respect that.
Deb
BTW Ken can't even turn on a computer (or for that matter find one buried under the mountain of paperwork on his desk), but I do keep him updated on many of the threads here. His particular favorite thread goes without guessing right now. He is really proud that ML took on the TGG experiment, he actually almost jumped up when he saw the picture slideshow of the experiment (which is quite a feat for a 300 lb diabetic man), and he is really glad that a proper unbiased experiment is being done away from our hatchery/farm.
