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I I I I I I I I I I I I I I I I I I I . Incubation Period Due to the fact that different egg shipments received by the FRH had varying water temperatures, comments will be limited to total hours it took to hatch the fry rather than using temperature units as the measurement of hatching time. In 68-700 F water, hatching starts about 80 hours after spawning and lasts up to 144 hours. CHEMICAL TREATMENTS FOR FUNGUS Formalin Eggs were treated with 1,667 ppm formalin at 68-700 F the day after spawning until eyed. Both a flow-through and a dip treatment were used at this concentration for 10 minutes each. Due to the quantity of dead eggs in all of the shipments of pikeminnow the FRH has received, fungus was almost impossible to control with only formalin treatments. If formalin is used, an investigative new animal drug (INAD) permit must be obtained to use on pikeminnow eggs. Hydrogen Peroxide Hydrogen peroxide was used to treat razorback sucker but not pikeminnow at the FRH. Dosage on razorback eggs, not eyed, was 500 parts per million for a 10-minute dip treatment. Malachite Green Malachite green was used on pikeminnow eggs for only one year because federal approval was denied in following years. The FRH used a dip treatment of 5 parts per million for 30 minutes in 67-720 F. Malachite green works extremely well in reducing fungus, but obtaining an INAD permit is very difficult. Extra caution needs to be used when dealing with this chemical. FACTORS AFFECTING EGG DEVELOPMENT AFTER SPAWNING Temperature Eyed eggs put into 530 and 600 F water stopped development and eventually died. Eggs exposed to abrupt temperature change (from 680 F to 530 F water and back to 680 F water within minutes) did not survive. Light It is generally recommended to protect all eggs from direct sunlight or artificial light until hatch-out, but there is no known information on this topic for pikeminnow. Movement . There was no determination as to when the sensltIve stage starts and ends. The recommendation is that once eggs have been transported and placed in egg-holdinglhatching containers, they should not be moved again. Oxygen No direct studies were done on oxygen usage but, as a precaution against oxygen depletion, an airstone connected to an aquarium pump was put into each hatching container. Make sure the 5