In fact the Solunar theory was even developed by a fresh water fisherman (John Alden Knight)
He published the first Solunar tables early last century. He was a keen fly fisherman and was looking for ways to predict bite times when you don't have tide times as a deciding factor. So he took a step back and looked at what's causing the tide times in the first place and found that sun, moon and their gravitational forces have an even stronger direct influence on all animal feeding behaviour. The whole food chain in nature is pumping along those rhythms of sun and moon.
a snapper a day keeps the doctor away