SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/fish-tank-cover

Why put a cover on a fish tank?

It keeps fish from jumping out.

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  1. It stops fish from sleeping
  2. It keeps fish from jumping out ✔
  3. It makes the water saltier

Why: Fish can jump from uncovered tanks. Rutgers says a cover should not completely seal the tank because air exchange is important for fish respiration and water quality.

Huh, didn't know that: An opaque cover can reduce algae growth, but it must not prevent fish from seeing their food.

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Why did the cat sit by the fish tank? It was hoping for a little fin-tertainment.
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References

Answer: It keeps fish from jumping out. Fish can jump from uncovered tanks. Rutgers says a cover should not completely seal the tank because air exchange is important for fish respiration and water quality.

  1. Rutgers NJAES: Introduction to Aquaponics Systems njaes.rutgers.edu/fs1351
    Covers or netting made of waterproof materials will keep the fish in the tank
    Checked 2026-10-11.
  2. UF/IFAS Extension FA124: Responsible Aquarium Fish Ownership ask.ifas.ufl.edu/publication/fa124
    Aquariums should be covered to prevent fish from jumping out.
    Checked 2026-10-11.

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