How Do I Prevent Fish From Jumping Out of My Reef Tank?

The best way to prevent fish from jumping is using a mesh lid or screen top combined with reducing stress factors. Many reefers have lost expensive fish to "carpet surfing" — here's how to protect your investment.

Physical Barriers

Mesh Screen Lids

The most effective solution is a fitted mesh screen lid. These allow light and air exchange while preventing jumps:

• DIY option: Build a frame from PVC or aluminum and stretch fiberglass or nylon mesh
• Commercial options: Companies like Artfully Acrylic and ClearView Lids make custom-fit screens
• Material: ¼" mesh is fine for most fish; use smaller mesh for tiny fish or wrasses

Covering Gaps

Even with equipment cutouts, minimize exposed water surface:

• Use foam strips around overflow boxes
• Cover gaps around power cords and plumbing
• Install eggcrate or mesh sections for odd-shaped openings

Reduce Jumping Triggers

Fish jump for reasons. Address the root causes:

Water Quality

Poor conditions stress fish and trigger escape behavior:

• Keep ammonia and nitrite at zero
• Maintain stable temperature (75-80°F)
• Test regularly and track parameters with the ReefBay app

Aggression

Bullying causes panic jumping:

• Research compatibility before adding fish
• Provide adequate hiding spots
• Watch for chasing behavior at feeding time

Startling

Sudden scares cause reflexive jumps:

• Move slowly near the tank
• Avoid tapping glass
• Keep loud activities away from the tank
• Use a ramp-up schedule for lights to avoid sudden brightness

Known Jumpers to Watch

Some species are notorious escape artists. If you keep these, a lid is essential:

• Wrasses – Especially fairy wrasses and flasher wrasses
• Firefish – Dart when startled
• Jawfish – Jump when scared
• Blennies – Some species are skilled jumpers
• Dartfish – Built for launching out of water

What To Do If a Fish Jumps

If you find a fish on the floor:

1. Return it to the tank immediately – even if it looks dead
2. Keep lights dim to reduce stress
3. Monitor for injuries over the next few days
4. Fish can sometimes recover even after several minutes out of water

Prevention is far easier than rescue. A quality mesh lid is a small investment compared to losing a prized fish.