Why is my Java fern dying?

Two possible reasons your Java fern might be dying are a lack of nutrients and too much light. Immediately check if the fern’s rhizomes are covered with substrate, hindering the plant from absorbing nutrients.

Next, check if the tank’s lighting is too bright for them. Generally, you shouldn’t expose Java fern to more than 1.5–2 watts of light for each gallon of water.

If your Java fern is dying, here’s what you can do to save it:

  • Make sure its rhizomes are uncovered
  • Remove algae from the tank
  • Add liquid fertilizer to the water
  • Increase CO2 level by adding yeast into the water
  • Dim the lighting
  • Limit exposure to light to 6-8 hours each day