Are you sure the hatchery said the FHM eat FA. No ones else here reports that FA feeding activity. Since your trout are all naturally fed they will eat some FHM depending on size of trout and abundance of FHM, It is hard to tell how many FHM the trout are eating. Minnow predation could be greater during cold weather.

If you use G.Clean Make sure it is GC Pro. Regular G.Clean is 1/2 as strong as GC Pro. In some areas Phycomycin is cheaper than GC Pro. Yes remove FA then apply peroxygen product liberally. Do some test areas to see how much does the best job. Adding bacterial products a few days after peroxygen can be beneficial.

Keeping the dye fairly dark as timshufflin does may also work for you. Killing lots of algae with algaecide will cause extra DO loss due to algae decomposing. Also using dye esp at higher rates will also reduce natural photosynthesis and less DO produced during the day hours. During cloudy rainy weather low DO could become problematic.

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