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acre ponds at a density of about 20,000 larvae per pond (50 - 100 thousand per acre). Ponds are fertilized with alfalfa pellets and superphosphate two weeks prior to receiving larvae to produce natural feed for larval fish. Ponds are fertilized again with alfalfa pellets one week after larvae are introduced. Fish are fed a catfish starter diet (sizes 1-3) made by Rangen@, that is enhanced with spirulina and krill and then switched over to the razorback diet once they are large enough to eat Imm crumble. Fish are fed twice a day by hand, four days a week at 2.5-6.0 % body weight. Feed ration is decreased if excess feed is seen remaining on the pond bottom following feedings. Fish are not graded or sorted during this grow-out period. Razorback suckers are harvested in the fall by draining ponds completely. Fish are sorted at harvest and distributed to other facilities for further grow-out depending on current size requirements. Razorback suckers are on average 1 00 - 200 mm TL after the first growing season and generally take 12 -18 months for a majority of the fish to reach 300 mm TL. There are 16 different species of fish maintained at Dexter National Fish Hatchery and having sufficient pond space to grow out separate groups of fish is the limiting factor for production of razorback suckers at this location. Grand Valley Native Fish Facility The Grand Valley Native Fish Facility maintains its own brood stock in eight ponds located at the Horsethief Basin Wildlife Areain Grand Junction, Colorado. Fish are spawned on site and larvae are reared indoors in fiberglass tanks at the 24-Road Fish Hatchery in Grand Junction. The 24-Road Hatchery consists oftwo separate recirculating systems that operate using de-chlorinated city water and two large fluidized- bed sand filters and rotating-drum filters for waste removal. Fish are held in 4-foot (n=78) or 8-foot (n=14) diameter fiberglass tanks. Larval fish are started on prepared 12