Tanvir

Algae rarely harms shrimp directly. Heavy growth is a message about balance rather than a danger: too much light, too many nutrients, usually both. Worry when it covers plants thickly enough to shade them, when hair algae forms mats that can trap shrimplets, when the water itself goes green, or when it grows straight back after cleaning.

You have been removing their food every weekend. Dwarf shrimp graze more or less all day on biofilm, the thin layer of microorganisms and algae that grows on every surface, plus soft algae on plants and rock and glass. For shrimplets especially that is most of the diet.

So a spotless tank is a worse home than one with a light coating of growth. Keep the back wall and a rock or two uncleaned on purpose, scrape only the front pane, and stop apologising for the green.