Grapefruit Acropora millepora
Acropora are the crown jewel of the SPS world. No other genus has the sheer number of species as Acropora and when reef aquarists talk about the requirements to keep an SPS system, they are talking specifically about the care requirements of Acropora. Having said that, Acropora are one of the most difficult corals to keep. They are highly sensitive to changes in water chemistry and require the most in terms of flow and light. Many experienced hobbyists have struggled keeping Acropora long term, but that is part of the attraction to this coral. Lastly, Acropora benefit greatly from a well established aquarium, preferably one that has been set up at least for 1 year. Please see below for additional care tips for Acropora as well as checking out our Top 5 Tips for setting up a reef.
Indo-Pacific - Acropora are found in the islands of the Indo-Pacific including Fiji, Tonga, Solomon Islands, and the Great Barrier Reef.
High lighting would serve this species well. Acropora can be kept under high output fluorescent bulbs (T5), but may benefit from more intense lighting such as metal halide (MH). It will likely change its coloration depending on the lighting provided. Acropora may require a longer acclimation period to intense lighting such as metal halides. Acropora are notorious for dramatic color changes depending on tank conditions, chiefly lighting. It is possible for some colors on Acropora to change entirely, for example red sections to turn green.Low Light
Low light translates to about 30-50 PAR
Medium Light is between 50-150 PAR
High Light is anything over 150 PAR
Lighting is a loaded topic, so for a more in-depth discussion of lighting, please see our Deep Dive article.
Strong water movement is recommended.
Like most coral, Acropora rely to a large extent on the products of their zooxanthellae, however, in our experience, they also benefit from direct feeding. There are a variety of frozen fish foods available that make outstanding meals for Acropora. We like to feed a mixture of meaty rotifer-based foods with vitamin additives and highly unsaturated fatty acids (HUFA). The size of the food must be small enough that the polyp can fully ingest it. We like to use the cloudy supernate that forms after thawing out frozen food and using a turkey baster to spray it on the Acropora colonies.
This genus for the most part has been propagated extensively in captivity and is an excellent candidate for aquaculture. It is reasonable to believe that a sustainable harvest can be achieved in time.
A Word of Caution
Acropora spp. are some of the most common and prolific stony corals found on the reef. They are found in almost every kind of reef habitat and are highly adaptive. They can take on completely different shapes and colors depending on their location on the reef. You would think that they are extremely hardy and can be tossed into any reef setup, but that is not the case. They are sensitive to water quality, susceptible to infections such as rapid tissue necrosis (RTN), and require plenty of light and water flow. If provided favorable conditions though, Acropora will reward the aquarist with beautiful color and rapid growth.
Proper acclimation is extremely important considering the stress imposed on the animals by the shipping process. Please take a moment to review our Acclimation Guide.
The images were taken with a Canon 5D mk II and 100mm macro lens under T5 Fluorescent lighting. Quite a lot goes into how we go about shooting the corals and anemones you see on Tidal Gardens. For an in-depth look at our methods, check out our comprehensive Reef Aquarium Photography FAQ.