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feeds immediately after swim-up and fed exclusively razorback feeds made by Silvercup@. Fish are started on a 0-250 micron razorback diet for the first 10-12 days and then fed with gradually increasing sizes of feed. This razorback diets is specially sifted by Dr. Rick Barrows (USDA Hagerman experiment station, Idaho), Fish are fed approximately 7.0% body weight per day initially and then gradually reduced to 1.5 % body weight by the time they reach the 300 mm TL target size. Fish are fed seven days a week using 12-hr belt feeders, Razorback suckers are sorted after three months and culled to about 4,000 fish per family lot. Culled fish are stocked into leased grow-out ponds. Stocking densities for larvae in these ponds is based on previous stocking and harvest rates and is pond specific. Grow-out ponds are harvested periodically using Fyke nets or trap nets and fish of the target size are stocked. Disease problems, water quality problems, and difficulty in removing all of the fish are challenges for grow-out of razorback suckers in these natural ponds, Fish reared in the 24-Road facility are sorted again at four to five months of age into small and large size groups to obtain more uniform growth rates. Batch estimates of fish weight are done every month for each tame A group of fish are weighed and counted to give an average weight for the tank with lengths estimated based on a length/weight chart. The biggest difficulties for growing out razorback suckers at the 24-Road Fish Hatchery are insufficient space and water flow (oxygen) to grow fish to the target size. At the Horsethief Basin Ponds where broodstock are reared, diseases such as Ich are problematic because water is pumped directly from the Colorado River. 13