Acanthastrea echinata

ACANTHASTREA 

Acanthastrea corals, sometimes referred to as starry cup corals, are typically large encrusting species with a wide variety of colors. They have 25 species within their genus and have large feeding tentacles. They are very fleshy with thick walls producing lots of concentric folds giving them a “wrinkly” look. These corals do best when they are fed, we have found that with our daily feedings of mysis shrimp and calanus they tend to do better and grow faster. Usually when people struggle with Acanthastrea it is due to a lack of feedings.

Acanthastrea is often confused with Micromusa as they share very similar looking species. The most noticeable difference at first glance are the size/shape of the feeding tentacles and size of their polyps. With Micromusa having smaller and less aggressive polyps. Acanthastrea have been known to produce long stinging and feeding tentacles making them a more aggressive neighbor who needs space.

WATER CHEMISTRY

Acanthastrea are very forgiving when it comes to water chemistry. It makes it a good coral for beginners so long as they keep on top of feeding! We have found they even tend to prefer dirtier waters. While we have our preferred parameters for Alkalinity, Phosphate, and Nitrate, Acanthastrea  will do far better in your system if you just focus on keeping the water chemistry stable. If your Alkalinity, Phosphate, or Nitrate is out of line, our recommendation is to get it back to your target levels as slowly as possible.

The parameters we aim for are:

We maintain these levels by use of dosing pumps, with Brightwell Aquatics Reef Code A and Reef Code B.

It's important to understand that these are the levels that we aim for in our systems. However, that doesn't mean they are the right levels for your system. All aquariums are different and your system may naturally fall on a different balance. You're better off working with the balance your system tends towards than trying to force the same levels that we run.

FLOW

In terms of flow Acanthastrea corals will need to be kept in a moderate flow area. Too much flow causes the flesh to recede closer to the skeleton so they lose their “puffy” appearance. In turn, the coral will not get its proper nutrients as now their feeding tentacles will not extend as much. Too little flow can cause detritus build up, and no flow to reach the bottom of the colony,potentially leading to tissue death.

LIGHTING

Acanthastrea are not picky with lighting as they are with flow. They tend to be happiest with moderate lighting but are more concerned with flow than light. As with many corals, too much light can cause discoloration and receding flesh. As we’ve mentioned before, these coral can be trained for higher PAR, but if this is your wish we recommend doing it slowly as the potential for bleaching is high.