Why a cover can help
A lid slows evaporation and can reduce the chance that shrimp climb out when water quality or conditions are poor. It also limits dust and helps keep curious pets away from the aquarium.
Covers vary: a tight glass lid may hold heat and condensation, while a mesh cover allows more evaporation. Choose based on room temperature and tank equipment.
Manage top-offs deliberately
Evaporation leaves dissolved minerals behind, so topping off with mineralized water can gradually raise concentration. Many keepers use purified water for evaporation top-offs, then restore minerals through planned water changes.
Do not seal an aquarium airtight. Maintain suitable gas exchange and check that cables and airline tubing do not leave large escape gaps.
For your own tank
Mark the normal water line and check it at the same time each week. A sudden drop can indicate evaporation, a leak, or a change in room conditions. Refill slowly with appropriate water and keep cable openings small without sealing ventilation.
Use these as general hobby references. Test your aquarium and confirm product guidance before making changes.