How to Manage Euphyllia Flatworms in your Reef Aquarium

Dealing with Euphyllia flatworms (specifically targeting corals like torch, frogspawn, and hammer corals) in a reef aquarium can be challenging. These flatworms often irritate coral tissues, leading to poor coral health. Here’s a step-by-step guide to help you get rid of them:

1. Manual Removal and Dips

• Coral Dip Treatment:
  Use commercial coral dips (like Bayer, CoralRX, or Revive) to dip infected corals.
  Instructions:
1. Prepare a dip according to the product's directions in a separate bucket.
2. Submerge the affected coral in the dip for 5–10 minutes.
3. Gently shake or blow water on the coral (with a turkey baster) to dislodge flatworms.
4. Rinse the coral in clean tank water before reintroducing it.
• Manual Inspection:
  During the dip, inspect for any flatworms still attached, and remove them with tweezers or a soft brush.

2. Biological Control

• Predatory Fish or Invertebrates:
  Some species naturally feed on flatworms, but success rates may vary.
• Wrasses: Six-line, yellow coris, or melanurus wrasses often prey on flatworms.
• Dragonface Pipefish: Known to pick at small pests but need a well-established reef.
• Scooter Blennies or Mandarins: May nibble on flatworms, but this isn't guaranteed.

3. Chemical Treatments (Tank-Wide)

• If manual and biological control isn't enough, consider using flatworm-targeted chemicals (e.g., Flatworm Exit by Salifert).
  Caution:
• Treat only if necessary, as flatworm die-off can release toxins.
• Perform a large water change (20–30%) after treatment.
• Use activated carbon to absorb toxins post-treatment.
• Remove vulnerable inverts temporarily, if needed.

4. Improved Water Parameters and Maintenance

• Reduce Nutrients: Keep nitrate and phosphate levels low to inhibit flatworm proliferation.
• Increase Flow: Euphyllia corals can tolerate moderate water flow. Proper flow discourages flatworms from settling on coral tissues.
• Siphon Regularly: If you spot flatworms, use a siphon to remove them during water changes.

5. Quarantine Protocols

• Always quarantine new corals for 2–4 weeks and dip them before adding them to your main display to prevent future infestations.

With a combination of methods, you can control and eventually eliminate Euphyllia flatworms. Regular observation and maintenance are crucial to prevent reinfestation.