Choose a viewing area
Many keepers clean the front glass to see the aquarium while leaving parts of the sides, back, plants, and hardscape alone. Shrimp can continue grazing away from the cleaned pane.
Use a tool appropriate for the aquarium material and rinse it before use. A trapped grain of substrate can scratch glass or acrylic.
Avoid chemical cleaners
Do not spray household glass cleaner near an open aquarium or use a cloth that may carry residue. Keep soaps, fragrances, and cleaning agents away from tank water.
If a scraper is needed, follow its instructions and keep the blade away from seals and silicone. Work slowly so shrimp are not trapped against the glass.
Keep the goal practical
A thin film on an aquarium surface is not automatically a problem. Remove growth that blocks viewing or equipment, then observe whether the colony still has plenty of mature surfaces.
Do not add extra food just because a cleaned pane looks bare. The aquarium contains many other places for biofilm and natural grazing.
Use these as general hobby references. Test your aquarium and confirm product guidance before making changes.