Aiptasia Anemone: Aiptasia pallida or A. pulchella

Phylum: Class: Order: Family: Genus: Species:
Cnidaria Anthozoa Actiniaria Aiptasiidae Aiptasia L. pallida or L. pulchella

Aiptasia are small light brown anemones of the species A. pallida and A. pulchella.  They are semi-transparent (translucent), hence the common name of Glass Anemone.  The adult anemones have a relatively long slender stock about 1-2″ in length with tentacles that are 1 to 1.5″ long.  The tentacles may have white bands around them as shown in some of the pictures here.  They are photosynthetic, but will also eat meaty things that are small enough for them to catch.  Like all anemones, their tentacles contain stinging cells to stun and capture prey and to wage war when necessary on neighboring invertebrates. The stalk is always attached to a hard substrate, usually in a crevice.  This allows the anemone to quickly withdraw into the hole when danger approaches.

Aiptasia reproduce through the process known as pedal or basal laceration which occurs when baby anemones develop from small bits of tissue left behind as the parent anemone wanders around.  This allows the Aiptasia anemone to reproduce quite rapidly.

There are a number of species of Aiptasia, but the two listed here L. pallida mainly from the Atlantic Caribbean region and L. pulchella from the tropical Pacific seem to be the most commonly seen in the hobby.  In any case, differentiating between the species is almost impossible and of little practical value since they all pretty much look and act the same.

Aiptasia anemones are sometimes confused with Majano anemones, but the Majano has much stubbier tentacles, often with bubble tips while the Aiptasia has long slender tentacles.  Aiptasia are also always a translucent brown color while Majano most often have a green coloration.

 Open Majano Anemone Database Entry 


Good or Bad?
Aiptasia anemones are BAD!  A couple of anemones are not a big deal except that they quickly spread.  They pack a powerful sting that can irritate or kill desirable corals and clams in the tank.  Aiptasia are common pests that most hobbyists have to deal with eventually.  Consider it a rite of passage in the hobby.  Unfortunately some unscrupulous or unwitting LFS will even sell ‘anemone rocks’ which are rocks overrun with Aiptasia.  The important thing is to deal with Aiptasia when you first recognize them in the tank.  They reproduce quite rapidly and as their population explodes, it becomes harder to eradicate them.

What Do You NOT Do?
As noted above, Aiptasia asexually reproduce in the reef tank by basal laceration.  Basically small pieces of the anemone that come off as the anemone moves about grow into new anemones.  If you take your frustrations out by trying to maim, chop, cut, scrap or otherwise mechanically torture, kill or remove them, you are basically just propagating them as the tiny left over pieces can grow into new anemones.

What Do You Do?
Aiptasia is most easily controlled when first observed in the tank.   Over time, they will spread and make eradication harder.  New live rock and corals should be inspected before placing in the tank though it can be very difficult to spot the small Aiptasia, so this only gets you so far.  What you don’t want to do is to try to physically remove them as any pieces of tissue left will form new anemones.  Control typically takes two main forms:

1) Chemical Control – The anemones are assaulted with an injection, feeding or slathering of something that will cause it’s death.

  • Inject with a store bought product.  There are products on the markets such as Aiptasia Stop which is a concoction of pepper juice that when injected into the anemone using a syringe, rapidly kills it.  I have used this product and it works well when it can be injected.  It is stated to be safe to other tank inhabitants and I have used it around clams, corals, etc. without any harm being done so their claims seem to have merit.
  • Feed it something toxic.  Joe’s Juice is a store bought mixture that is fed to the anemone and subsequently kills it.  Though I haven’t tried it, I have heard good results with this product and it is easier to feed Aiptasia than it is to try to inject it.   Another similar product is Aiptasia-X.
  • Inject or slather with a homemade caustic solution made from a concentrated Kalk solution or similar.
  • Inject with hot (near boiling) water.
  • Inject with lemon juice, vinegar or similar.

The problem with the injection approach is that it is difficult to get to some anemones to inject them, and they don’t just sit around waiting for you to complete the task.  They are very adept at retreating into the rockwork.  It does give you a certain amount of satisfaction when you do finally nail them however.  This approach also does not help much with the small ones that are too small to inject.  The feedable products like Joe’s Juice is probably the best chemical solution.

If there is only a couple of Aiptasia and the rock is easily removed from the tank or is fresh live rock going into a tank, I have had success just using an eye dropper to drop some straight vinegar on them while stirring them with a toothpick and then letting them sit for a few minutes before returning the rock to the tank.

Aiptasia anemone

Hitchhiker Found!

Aiptasia and Vinegar

You Can Run, But You Can’t Hide From The Vinegar


2) Biological Control – The approach taken here is to introduce animals into the tank that will eat the Aiptasia.  There are not a lot of animals that like to eat them however and those that do like butterflyfish often like to eat other things in the reef tank that they shouldn’t.

Copperband butterflyfish (Chelmon rostratus) are sometimes good Aiptasia eradicators and other times they are completely worthless.  It appears to depend upon the specific fish.  I know LFS that routinely rotate Copperbands in their tanks to keep the Aiptasia in check with good results.  I have never personally observed my Copperband butterflyfish eat Aiptasia.Copperband butterflyfish are generally reef safe, but will absolutely take care of any fan worms in your tank and there have been reports that they may eat corals that look similar to Aiptasia, such as yellow polyps, so that is something to watch for if you have these in your tank already. Open Copperband Butterflyfish Database Entry
Copperband Butterflyfish

Copperband Butterflyfish

Other Butterflyfish such as Raccoon Butterflyfish will often eat Aiptasia, but they tend to eat other small soft corals as well and may harass clams, so they are not generally recommended for use in a reef tank.

Raccoon Butterflyfish

Peppermint shrimp Lysmata wurdemanni are small pink to reddish lightly stripped shrimp that sometimes do a good job on the Aiptasia.  I have found that some shrimp are voracious eaters and some seem to pay the Aiptasia no attention at all.These have done the job in my tanks and appear to be harmless to the desirable corals and clams for the most part. The larger adult shrimp appear to be better Aiptasia eaters than the juveniles per my own experience.  The shrimp may also not tackle the very large Aiptasia in the tank.  If you have fish such as some wrasses that consider shrimp as food, this may not be an option for you to try. Open Peppermint Shrimp Database Entry

Peppermint Shrimp

Nudibranches of the species Berghia verrucicornis from Caribbean waters are sometimes used to eat Aiptasia.There is much speculation as to which ones really work and there appears to be much confusion over which ones are which.  In any case the nudibranches will die as soon as their food supply is depleted which is unfortunate.  For this reason, some people chose not to use them or propagate Aiptasia in a separate tank to feed them once the Aiptasia are eradicated from the display tank.Click on the button for an excellent article on Berghia verrucicornis by Anthony Calfo in ReefKeeping Magazine. Berghia verrucicornis Article
Berghia verrucicornis

Berghia verrucicornis

3) Death by Hydrogen– I should probably mention that a 3rd option exists.  Some enterprising individual has developed something called the ‘Majano Wand’ that can be used to kill Majano anemones that works equally well on Aiptasia anemones.  The device is an electric wand that uses a low voltage electrical current to create hydrogen gas from the saltwater.  Since anemones are largely composed of saltwater, this basically causes the anemone to explode from within.  Though not a low cost solution, it seems to perform well based on reviews and may be a viable option to consider for a larger tank that is battling a large quantity of Majano or Aiptasia.

Two Photos courtesy of Haplochromis and Dr. James P. McVey, NOAA Sea Grant Program which are tagged individually.  The picture of the Berghia Verrucicornis is from Anthony Calfo’s article.   All other photos by ReefCorner © All Rights Reserved