While this species is called the bubble-tip anemone in the hobby, many of them don't have bubble-tipped tentacles. While many of them do bear tentacles that have bubble-like swellings near their ends, many others lack the swellings, and instead have longer, thinner tentacles. These can easily be mistaken for a different species altogether, as they resemble most any other anemone with plain, long tentacles. Having or lacking bubbles isn't always permanent either, as they may come and go in some cases. For the most part, specimens that have relatively short tentacles may or may not develop or retain the bubble-like swellings over time, while those with long, thin tentacles typically lack them entirely.
BTAs come in a range of colors from brown to green and orangish to red, with the red ones often being called rose anemones. They can also vary greatly in size when mature, with some growing to no more than a few inches across and having relatively short tentacles, and others getting absolutely huge. The disc of occasional specimens may grow to over a foot across, and these can develop tentacles that are several inches long, too.
BTAs are always found attached to solid substrates, and usually with their base down in a hole or crevice. When living in shallow waters they often occur in large groups and are tightly spaced, making some areas look like they're covered by one giant anemone with thousands of tentacles. In such cases the anemones generally stay smaller and have shorter tentacles, but not all of them live in groves, as some live alone or in smaller groups. This is especially true when they are living in deeper, dimmer waters, where they also tend to grow to larger sizes and indeed do have longer, thinner tentacles.
When it comes to reproduction, BTAs do have separate sexes. Some are male and some female, and they will spawn from time to time by releasing large numbers of sperm and eggs into surrounding waters. Some of these gametes will end up meeting each other, and once fertilization occurs, the eggs will develop into larvae. Then, these will eventually settle to the bottom and begin to grow into adult anemones, which can start the reproductive cycle all over.
Sexual reproduction is important because it allows the genes of different anemones to mix, thus ensuring that there is some diversity in a population. But, BTAs can also reproduce asexually. Most other species of anemone only reproduce sexually, but BTAs can make more of themselves without the use of any sperm or eggs to produce genetic clones. (Aquarium Invertebrates: Entacmaea quadricolor: The Bubble-Tip Anemone, By James W. Fatherree, M.Sc.)
You can also cut the BTA in half with good success. My OBTA naturally split several months ago into 4 separate clones. This is one of them that has grown to almost 12" in diameter. My black Onyx Clowns host in them and produce eggs regularly.
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BeakerBob - Past MMMC Club President, current Board Member
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