The Ultimate Guide to Dealing with Aiptasia in Salt Water Aquariums

Pest Removal
Aiptasia inside Fishtank

Aiptasia, the bane of our existence as saltwater tank owners. We have customers weekly, sometimes daily, ask about how to get rid of this annoying pest. Well we are out to answer that question once and for all.

What is aiptasia?

Aiptasia is an invasive pest anemone that is very hardy, prolific and poisonous to other corals.  It will outcompete most corals, soak up nutrients, food, and annoy or kill other corals near it. It serves a key role in nature but in aquariums it is an uninvited guest.

Why is it so bad?

There are many reasons you don’t want this pest in your tank. The major ones are…

  • It stings.  It has cells called nematocysts at its tips that annoy or kill other coral.  It won’t bother humans usually but small invertebrates, fish and other coral are either annoyed or killed by it.
  • It breeds fast.  One aiptasia today can mean a tank over run in a week.  The reproduce sexually and asexually so only one is needed to reproduce.
  • Spores.  When you try and remove or kill aiptasia, it releases spores that spread throughout your tank spreading them even faster.
  • It’s hard to kill. aiptasia is one of the hardiest anemones that exist. It will be the last thing to die in your tank… if it ever does. They are the cockroaches of the saltwater pest world.

So basically it kills things and spreads fast, is hard to kill, and in turn kills other things. Add to that, you only need to miss one tiny one on the back of a piece of rock you cant see to start the cycle all over again.

How do you identify it?

Aiptasia is a small, translucent anemone.  It is a small stock with a disc face, surrounded by small tentacles.  Different species are tinted different colors from a pale yellow to brown.  The picture is a typical aiptasia. A quick google search will find you millions of examples but they all look about the same.

It usually pops up unannounced inside a polyp coral like zoa’s or in crevices in your rock work. If you didn’t put an anemone there and a tiny dime sized one appears out of nowhere… it’s probably aiptasia

How do you kill it?

This is the million dollar question. While very resilient, they aren’t that hard to kill. The key is killing them in such a way that they do not release their spores. That means killing them fast or smothering them quickly.

The second, and more difficult part is killing them all before they start reproducing again. A herculean task since they can sometimes appear between rocks where it isn’t visible.

We have broken strategies down into three categories.

  • Animals and Livestock
  • Chemicals
  • Equipment
  • Dip

Animals and Livestock

This is listed first because it might be your best bet. A predator that can scour your tank 24/7 will always be more effective in the long run than us trying to hunt and peck our way through every crack and crevice in the tank.

There are quite a few predators of aiptasia.  Fish that snack on them include aiptasia eating Filefish, Copperband Butterfly Fish, Bristletail Filefish, Pufferfish, Scat Fish amongst others.  The usefulness varies depending on the size of the tank, other tank mates, if you have coral etc.  A bit of research goes a long way. 

The other end of the spectrum are invertebrates.  Peppermint shrimp and Berghia Nudibranchs.  It’s one or the other as well, peppermint shrimp will eat the Berghia.

Berghia Nudibranchs work amazing.  They are tiny and reproduce quickly.  But they are small and only eat Aiptasia, which means as soon as they are all gone, they will starve to death.  The real downside is that most wrasses, peppermint shrimp, and a variety of other livestock will eat them before they can do their job.  They are also difficult to come across and a bit expensive when you do find them.

Peppermint shrimp are hit and miss.  It’s mainly because there are quite a few Peppermint Shrimp species that are lumped in the generic category of “Peppermint Shrimp”, but only one eats aiptasia.  Lysmata wurdemanni is the specific species that does eat aiptasia.  But even to the most skilled eye, it’s very hard to tell the difference between the different species.  Another issue is that the Lysmata wurdemanni might not be reef safe once the aiptasia is all gone and have been seen eating euphyllia corals (hammers, frogspawn, torches etc).


There are quite a few options in this category.  Aiptasia-X, F-Aiptasia, Joe’s Juice, Aiptasia Away etc…  They all are basically the same thing in different concentrations.  It’s a glue that globs up underwater and doesn’t trigger the aiptasia spore response.  The glue basically smothers the anemone and kills it off.

Injecting lemon juice, hydrogen peroxide or even boiling hot RO water will do the same thing.  There is a bigger chance of inciting the spore response if you “miss” and don’t inject it at the base before the anemone retracts.

The pro’s of chemicals are that they definitely work.  The biggest issue is you can never see them all.  There inevitably will be a small anemone hidden in your rock work, or sump that will keep pumping out spores making it an ongoing issue.


While maybe the least practical, this category is definitely the most… fun.  There are a few different pieces of equipment, from lasers, to uv lights, to electricity charged wands.  

The Reef Delete UV Pest Eradication tool from ITC is a uv laser to shut them down and kill them.  It can be used under water but it is very expensive.  

There are quite a few 20-40 watt lasers for sale now that are marketed at killing pest anemones.  These definitely work but are pretty dangerous.  You must wear special goggles and be careful of stray fish being wounded or blinded.  Hearing the rock pop and bubble as that annoying aiptasia is roasted is very satisfying though.

Lastly is a Majano Wand.  Majano is another pest anemone that is similar but not as bad as aiptasia to deal with.  The wand is an electrically charged wand that basically electrocutes the anemone.

All the equipment listed works exceptionally well but suffers from the same issues the chemical removal does.  You have to be able to see it to kill it, and in most tanks that is not possible.


This is like telling someone to close the barn door after the horses have been let out. But your most effective option is to dip all your coral in advance. Coralrx, Coral Dip, and many other brands will kill the aiptasia before it has a chance to root in your tank. Even if you already have aiptasia, start dipping to stop future infestations from occurring.

Final Advice

So… what do we advise? A combination of dipping, livestock and chemicals. Dipping all coral, a predator or two for maintenance and a good chemical for all the aiptasia you can see and have access to.

An Aiptasia Eating Filefish or a Copperband Butterfly fish, will usually make short work of the pest when it can find it. A peppermint shrimp also works well. 

As far as the chemical options go, we recommend one of the products you buy. You need a clumping agent to smother the aiptasia and stop the spores from being released. We haven’t noticed major differences in the brands so whatever you can get your hands on works fine.

The combination of the natural predator and some sort of aiptasia killing gel is enough to handle it for most people.  One of the biggest things you can do to help yourself is dipping. Try and stop the little devil in its tracks.

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