The problem with the so-called “rainbow” corals is that all the colors blend, and from far away, the coral looks almost brown. However, for The Carl Acropora, it is mostly green with purple tips. There is a darker green and a light green that adds some depth to the color. The purple tips have a hint of blue. There are also some hints of orange and yellow on the branches of the coral. Of course, the exact coloration can vary a lot depending on the tank the coral is put in. Acropora corals are found all over the Indo-Pacific. However, the coral frags sold here are aquacultured by ORA. This means that instead of being collected from the ocean, they are grown in aquariums and then fragged.
Like most Acropora, Carl Acros prefer medium to high light, with more intense light being very beneficial for the color of the coral. It is best to start this coral low and then slowly move it up to higher light. Eventually, you should get this coral into the 200-300 micromoles of PAR range for the best coloration. As for flow, this coral requires moderate to strong flow. Flow is not something you want to be cheap on when it comes to Acropora and SPS in general. While these coral do fine with moderate flow, you really should be providing quite turbulent waters.
Acropora contain photosynthetic algae called zooxanthellae. This algae provides the coral with most of its food. You can feed this coral with powdered coral food, but this is usually not all that beneficial. Instead, you should dose your aquarium with phytoplankton and add copepods for food. Also, ensure that your nutrients are in a good place. Ideally, it is best to keep your nitrates at 1-5 ppm and your phosphates just barely detectable. This will ensure that there is enough nutrients in the water for your corals to consume without much risk of algae growth. In aquariums with little to no nutrients, Acropora can lose color. On the other hand, having a proper amount of nutrients will promote brighter colors and more growth. Another way to promote growth is with higher temperatures. A reef aquarium should be kept between 72 and 78 degrees Fahrenheit. Leaning on the high end of that range can allow for faster coral growth and better coloration, but stability is more important than reaching a specific number.
Purchase Size: 1 – 2″
Placement: Middle to Top.
Lighting: Medium to high.
Flow: Moderate to strong
Parameters: 72-78° F, dKH 8-12, pH 8.1-8.4, salinity 32-35 ppt
Calcium: 350-450 ppm
Alkalinity: 8-12 dKH
Magnesium: 1,250-1,350 ppm
The Carl Acropora from ORA is aquacultured. Although aquacultured corals can cost more than corals collected from the wild, they can save money in the long run. Aquacultured corals are well adapted to aquarium lighting and aquarium conditions in general. This means that this coral is much more likely to do well in your aquarium than a wild collected acro. Aquacultured corals are also far less likely to carry pests, although you should still dip them to be safe. Whenever you can, you should always go with aquacultured coral over wild collected ones!