Quick Reference Guide: Top 10 Fish Species to Avoid in Reef Tanks

Even though they can be quite beautiful, some species are less than ideal citizens for a reef tank. See below for a list of our top non-reef-safe fish.

Lionfish (Pterois spp.):

• Reasons to Avoid:

  • Threats: Venomous spines pose risks to tank mates and handlers.

  • Risks: May overeat and disrupt the balance in a reef tank.

Triggerfish (Balistidae family):

• Reasons to Avoid:

  • Threats: Destructive behavior, can damage corals and rock structures.

  • Risks: Known to be aggressive, especially when defending territory.

Butterflyfish (Chaetodontidae family):

• Reasons to Avoid:

  • Threats: Many species feed on coral polyps, posing a risk to reef health.

  • Risks: Difficult to acclimate to captive diets, often leading to health issues.

Harlequin Tuskfish (Choerodon fasciatus):

• Reasons to Avoid:

  • Threats: Predatory nature, may harm smaller tank mates.

  • Risks: Requires a large tank, can be challenging to feed.

Snowflake Eel (Echidna nebulosa):

• Reasons to Avoid:

  • Threats: Can prey on smaller fish and invertebrates.

  • Risks: Known to escape tanks through small openings.

Moorish Idol (Zanclus cornutus):

• Reasons to Avoid:

  • Threats: Difficult to feed in captivity, often leads to malnutrition.

  • Risks: High mortality rates in home aquariums.

Foxface Rabbitfish (Siganus vulpinus):

• Reasons to Avoid:

  • Threats: Venomous spines, can cause harm if mishandled.

  • Risks: May nip at and damage corals.

Marine Betta (Calloplesiops altivelis):

• Reasons to Avoid:

  • Threats: Predatory behavior may consume smaller tank mates.

  • Risks: Sensitive to water parameter changes.

Blue-Spotted Jawfish (Opistognathus rosenblatt):

• Reasons to Avoid:

  • Threats: It may disrupt sand beds and burrow extensively.

  • Risks: Challenging to acclimate, prone to stress-related issues.

Freshwater Fish in Marine Tanks:

• Reasons to Avoid:

  • Threats: Incompatible with marine conditions, may introduce diseases.

  • Risks: Unable to thrive in the saline environment, often succumb to stress.

Handling with Caution:

Research is Key: Thoroughly research the needs and behaviors of any potential fish before adding them to a reef tank.

Compatibility Matters: Ensure compatibility with tank mates, considering both size and temperament.

Expert Advice: Seek advice from experienced hobbyists or aquarium professionals when considering challenging species.

Quarantine Procedures: Always quarantine new additions to prevent the introduction of diseases.

Conclusion: Choose Wisely for Reef Harmony

Careful consideration of fish species is crucial to maintaining a thriving and harmonious reef tank. Avoiding potentially harmful or incompatible species ensures the longevity and well-being of both the fish and the coral ecosystem.