How to deal with aiptasia infestation in a reef aquarium

What Are Aiptasia—and Why Are They a Problem?

Aiptasia are small, hardy sea anemones that belong to the family Aiptasiidae. In the wild, they’re typically found in shallow, sunlit coastal waters attached to rocks, coral rubble, or even man-made structures. They thrive in areas with moderate to low flow where food and detritus can collect. Like corals, Aiptasia host symbiotic zooxanthellae algae within their tissues, allowing them to generate energy from photosynthesis under aquarium lighting. In addition, they capture food particles/ plankton using their stinging tentacles, and uptake dissolved nutrients from the water. This dual feeding strategy makes them especially resilient, allowing them to survive in both nutrient-poor and nutrient-rich environments. Because they can tolerate a wide range of light, flow, and nutrient conditions, they are often among the first pests to colonize aquariums once introduced.

In aquariums, Aiptasia are persistent, fast-reproducing sea anemones that often find their way into reef tanks, usually hitchhiking in on live rock or coral frags. They grow rapidly sometimes up to 5 cm and thrive under a wide range of conditions.

What makes them such a pest?

• They have stinging cells (nematocysts) that can stress or kill nearby corals and invertebrates.
• They reproduce both sexually and asexually, fragmenting easily from even from a small tissue single cell (pedal laceration) so even minor damage during removal cause several new Aiptasia to grow and contribute to an outbreak.

• They compete with your corals for nutrients, light, and space, degrading the aesthetics and health of your tank.

Bottom line: As soon as you spot Aiptasia, it’s game on early intervention is your best defense.

 

Identification Tips

Look for:

• A translucent, tube-like stalk with long, slender tentacles, sometimes tan, brownish, or clear. Attachment to live rock, glass, or substrate, especially in low-flow areas. 

• Differentiation from similar pests like Majano anemones: Majanos have shorter, club-shaped tentacles and more bulbous bases. 

Early detection and accurate identification are key to successful control.

 

Proven Methods for Removal & Control

 

A. Natural Predators (Biological Control)

The availability of good Aiptasia bio control in Australia is lacking due to species availability and import restrictions.

True Peppermint Shrimp (High success): 
Peppermint shrimp are often recommended as a natural bio-control for Aiptasia. There are many Peppermint shrimp species worldwide and they don't all behave in a similar way. The shrimp species reported to be best for Aiptasia control is Lysmata boggessi  (sometimes misidentified and confuse with Lysmata wurdemanni) and is considered the most reliable in international guides at eradicating Aipasia. However, these species are native to the Atlantic and are not available in Australia due to strict biosecurity regulations. In Australian waters, the peppermint shrimp species you’ll encounter is Lysmata vittata, an Indo-Pacific species that is readily available through local suppliers. While its effectiveness against Aiptasia can be questionable and can vary between individuals, it remains the only peppermint shrimp option readily available in the Australian hobby. Because much online advice refers to non-local Lysmata species, reef keepers in Australia should be aware that L. vittata is the one they’ll be purchasing.    

If our Australian peppermint shrimp species alone do not control the infestation, pairing them with other methods can improve results.

Berghia nudibranchs- High success 
Aeolidiella stephanieae, formerly Berghia verrucicornis feed exclusively on Aiptasia and can actively locate prey even in hidden spots. They may have a slow start but are so effective at eradicating Aiptasia that they tend to starve to death after eradicating every single one in the tank. Berghia stephanieae, originates from the Atlantic and Caribbean regions, and also parts of the Mediterranean. These useful nudibranchs are not native to Australian waters, and there are no known wild populations present locally. They are most likely unavailable in our local hobby at this point in time. 

Copperband Butterflyfish (Chelmon rostratus)- mixed results-  use with caution 
Perhaps the most well-known Aiptasia-eating fish, the Copperband Butterflyfish has a reputation for picking at and controlling infestations. In the wild, it feeds on small invertebrates, worms, and coral polyps. While many individuals will target Aiptasia in captivity, success is inconsistent and some never touch them. Copperbands are also considered delicate: they can be difficult to acclimate to prepared foods, often suffer high mortality in inexperienced hands, and require spacious, stable aquarium. Even when feeding on Aiptasia, they may also nip at desirable corals, feather dusters, or clam mantles.

Stripey (Microcanthus strigatus)- mixed results- use with caution 
Native to Australian and Indo-Pacific waters, the Stripey is a hardy schooling fish sometimes observed grazing on Aiptasia. Reports from aquarists suggest it can reduce infestations in larger systems. However, Stripeys are opportunistic omnivores and may nip at corals, polyps, or clam mantles once the Aiptasia population declines. Their rapid growth and tendency to form shoals can also make them less suitable for smaller reef aquariums. Additionally, anecdotal reports mention that juveniles are better at targeting and eating Aiptasia than larger individuals. 

Aiptasia-eating Filefish (Acreichthys tomentosus)- High success- use with caution 
This small filefish is widely regarded as one of the most reliable biological controls for Aiptasia. Numerous hobbyist and literature reports confirm its strong tendency to target the pest, often even in cases where other predators fail. However, as with many opportunistic feeders, individuals may also pick at soft corals, LPS, or zoanthids once Aiptasia is eliminated. They are generally hardier in captivity compared to Copperbands, adapting well to frozen and prepared foods, making them more practical for long-term maintenance.

Conclusion: Peppermint shrimp should be tested as its the lowest risk and cheaper biological option available in Australia. While all three fish species mentioned can be used as biological control, the Aiptasia-eating filefish (Acreichthys tomentosus) is generally considered the most reliable and manageable option in captivity. That said, none pf these fish are 100% reef-safe, and you should should weigh the risk of coral nipping against the benefit of Aiptasia reduction.

B. Manual Removal (Caution Required)

• Removing Aiptasia by scraping or cutting them off may leave tiny fragments that could regenerate and potentially multiply (Not recommended)
• If you go this route, consider removing the affected rock completely and using tools; razors, bone cutters, then super glue to seal the area afterward. 

C. Targeted Chemical treatments 

When biological control isn’t suitable or when infestations are too widespread, you may want to use commercial formulations. These products are designed for direct application onto Aiptasia polyps and work by either smothering, chemically burning, or disrupting cellular processes. Each option has its pros and cons:

Commercial Treatments for Aiptasia

Most products are based on calcium hydroxide pastes that is injected onto the Aiptasia oral disk area

• Aiptasia-X (Red Sea)
• Blue Life Vet Aiptasia Control RX
• AquaVision Aiptasia Solution
• Maxspect Aiptasia Control
  
• Royal Nature Aiptasia Controller

Best-Practice Application Protocol for Aiptasia Treatments

Commercial Aiptasia solutions are only as effective as the way they are applied. Incorrect technique often leads to partial kills, regrowth, or accidental stress on nearby corals. The following protocol outlines the most reliable way to use products. Always refer to the manufacturers instructions of your particular product of choice. The following is a guideline only.

Step-by-Step Guide

1. Prepare Your Tools

• Fill the supplied syringe or pipette with the solution.
• Ensure you have good access to the target Aiptasia (a flashlight or magnifying glass can help for hidden ones).

2. Turn Off Pumps and Powerheads

• Stop all water circulation before treatment.
• This prevents the solution from dispersing and stops the Aiptasia from retracting due to flow disturbance

 

3. Approach Slowly 

• Hold the syringe steadily, approaching the Aiptasia gently to avoid spooking it and causing it to retract. 
• Avoid touching the tentacles as any contact can cause the polyp to retract before treatment.

• These solutions work when applied to the exposed oral disc. effectiveness will be severely impacted if the Aiptasia is retracted.

4. Target the Oral Disc (Mouth)

• Place the syringe tip just above the mouth opening (center of the tentacles).
• Slowly release the solution until the disc and surrounding tentacles are covered.
• With adhesive pastes (e.g., Maxspect, Blue Life RX), create a small “cap” over the polyp to smother it.

 

5. Wait and Observe

• Leave pumps off for 15–20 minutes to ensure the anemone ingests or is fully coated.
• You should see the polyp collapse or dissolve within minutes.

6. Aftercare

• Turn pumps back on after 15–20 minutes.
• Monitor nearby corals for any stress (e.g., closed polyps) and adjust flow to disperse residues if needed.
• Remove any loose tissue fragments with forceps, pipettes or turkey baster if visible to prevent regrowth.

7. Follow-Up

• Inspect treated areas after 2–3 days.
• Re-treat if polyps reappear or if smaller individuals nearby were missed.
• For heavy infestations, treat in batches (no more than 5–10 Aiptasia per session in smaller tanks) to avoid water chemistry swings.

 

Tips

• Precision is everything: Aiptasia can reproduce from leftover tissue. Direct hits to the oral disc are most effective.
• Less is more: Overdosing solutions in one session can affect water chemistry. Stick to the recommended dose.
• Combine strategies: Pair chemical treatments with biological controls (e.g., Lysmata vittata shrimp or Acreichthys tomentosus filefish) for long-term suppression.
• Prevention matters: Quarantine new corals and rocks to avoid reintroducing Aiptasia.

D. Household Treatments- use with caution 

Home remedies like Kalkwasser (calcium hydroxide), lemon juice, hydrogen peroxide or hot water delivered by direct injections (e.g., insulin syringe) were used by hobbyists to combat Aiptasia. These home treatments were reported to kill Aiptasia by some users. Note that Calcium hydroxide and lemon juice can impact the pH, so monitor carefully, and always turn off pumps during injection to limit spread. Extra care should be taken when handling a syringe with a needle to avoid harm and accidental injuries to the user and inhabitants. It is preferred to go with a proven method to avoid risks to the aquarium inhabitants and the user.