They are pretty interesting creatures nonetheless. They can clear a bloom in a few days and this seems particularly interesting use for them to improve water quality and produce food. Most species live for a 3 weeks or longer and so its a gravy train for any fish till they are gone. I think they are very interesting if an affordable source of cysts could be obtained. 24 grams/acre of cysts could yield for example more than 700 lbs/acre of shrimps if survival of shrimps were 70% to day 7 for example. If a person spend say $2 a gram for the cysts, the wet weight cost of the forage would be less than 7 cents a lb. With 14 days to finish them off, the average daily consumption could be 50 lbs/day. Maybe that consumption rate is too high and a small quantity is better. I imagine that panfish and minnows would just fill up on them. The goldilocks treatment would be where they were all consumed before dying of old age.
They are a very large creature considering what they are eating which includes very efficient filtration of bacteria, yeasts, phytoplankton, etc that are too small to observe without a microscope.
When I first built my pond I stocked my first FHM about 2 weeks after filling and it was at night. After releasing the minnows I was watching them swim off when I spotted something else. My first thought was a bullhead fry and then I realized it was ferry shrimp. In the western 1/4 of Kansas we have very high numbers of Playas and they are of course dry most of the time except after a good rain (not often here) and most contain ferry shrimp. I've never tried to raise any but it's amazing that it can be dry for several years then get a good, heavy rain and the Playas are full of ferry shrimp in just a few days.
