What kinds of adverse effects would I see if I have an LED lamp always on for red cherry shrimp aquarium? The aquarium has dark hideouts (under wood, plants) for them if they need darkness. I also turn the lamp to night mode at the moment. This question is not for my aquarium.
Shrimp are more active at lower lighting and during complete blackouts (nighttime).
If you would leave your light on for the entire day, they will go into hiding and become stressed. They will start losing color and eventually die.
Not only your shrimp will suffer but you will almost certainly get a lot of algae.
A source: http://www.redcherryshrimp.net/shrimp-information/beginner-guide-101/starting-out-with-red-cherry-shrimp-rcs/ + experience breeding and keeping shrimp