Aiptasia are small brown pest anemones that arrive on rock and frags, multiply quickly and sting nearby corals. While there are only a few, treat each one with an aiptasia treatment that you inject or cover it with. For a bigger outbreak, Berghia nudibranchs are the most reliable predator: they eat only aiptasia.
How to recognise them
Bulk Reef Supply describes aiptasia as small, invasive anemones, also called glass or rock anemones. They’re brown and translucent, with long tentacles, and retract into the rock when touched. They usually arrive on live rock, coral frags or other additions.
The problem is speed: Bulk Reef Supply says they reproduce rapidly and sting corals, causing stress and sometimes death.
A few: treat each one
Bulk Reef Supply lists products you inject or apply over each anemone, including Frank’s F-Aiptasia, Joe’s Juice, Red Sea Aiptasia-X and Maxspect Aiptasia Control. It recommends this for early infestations, and warns that too much solution can irritate the tank.
Treat every one you can find, then check again a week later for any you missed.
Many: bring in a predator
Bulk Reef Supply calls Berghia nudibranchs the most effective option, because they eat only aiptasia. Add a few at night after feeding; it says the problem is usually gone within one to two months. The catch: they’re tiny, need careful handling and die off once the aiptasia are gone.
Peppermint shrimp, aiptasia-eating filefish and copperband butterflyfish are also used. Check each one suits your tank and corals before buying.
Keep them out
Inspect new rock and frags before they go in. Keep a weekly pest check in your routine and treat anything new immediately, while it’s one anemone rather than a colony.
Common questions
Can I just scrape aiptasia off?
Scraping often leaves pieces behind that regrow. Treat or use predators instead.
Do peppermint shrimp eat aiptasia?
Some do. Results vary between individuals.
How long do Berghia take?
Bulk Reef Supply says one to two months for an outbreak.
Sources and limits
Last checked 13 October 2026. This guide brings together the published advice below. It can’t see your tank: if livestock is in distress, act first, then ask an experienced local shop or club, ideally with your test log to hand.
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