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Since Shad are also filter feeders, would you think they'd create a similar scenario?

You bet. Shad reduce the standing crop of phytoplankton and covert zooplankton into meaningful forage for predators. Larger shad eat detritus and algea outright. There are several benefits. Increased visibility favors predators. Reduced standing crop of phytoplankton makes the nighttime dips of DO more muted with higher lows. Lower standing crops of zooplankton mean less competition for DO as well. More DO means higher predator metabolism and of course the more they are inclined to eat the more they can grow.

I will mention that good visibility does not necessarily mean that water is infertile. If there is a good mix of organisms and their predators are not over-abundant, those organisms can crop phytoplankton at the rate it reproduces. A large standing weight of phytoplankton, though it is food, isn't really a good thing. It means that consumers are not abundant enough and the phytoplankton population consists of many aged individuals. These kind of conditions can lead to phytoplankton die-offs which can also kill the fish in the pond.