All combinations of colours can be mixed together from base, to tip, to polyp. In the wild, Acropora are generally found in shallower parts of the reef and therefor require medium to intense light in our aquariums (200-400 par). This means, they are also accustomed to strong water flow, flushing through every part of the coral. There are some acropora species which are found in deeper waters which tend to require less light, but still benefit from medium to strong flow. ‘Deep water acropora’ are recognized from their thin and delicate branch structures and ‘smooth skin’.
The most commonly discussed aspect of keeping acropora is attaining optimal colourization. Strong lighting, with a heavy blue spectrum, the right level of nutrients (NO3 and PO4) and micro/trace elements all play a part. For example, blue pigmentation is often associated with potassium levels, green with iron, etc. It is often noted that a certain acropora morphs can vary greatly in colouration from one aquarium to another. Generally, most Acropora and SPS corals will receive sufficient nutrients from the food we feed our fish, but some situations require supplementation of a NO3 or PO4 additive. Another easy solution is just turning the protein skimmer off for intervals at a time. Most micro and trace elements are provided in a good quality salt mix and can be maintained by regular water changes, however, there are many trace supplement products on the market. If you suspect your tank is suffering from low levels of trace minerals/metals, an ICP water test can be sent off and analyzed in a lab for a detailed report. To keep acropora thriving and growing in an aquarium environment, it is important to maintain a stable alkalinity between 7.5 and 8.5 dkh. The alkalinity or ‘carbonate hardness’ should not swing more than 1.0 dkh within a 24 hour period. We aim for 8.3- to 8.5 in our SPS coral system. Other key parameters include calcium and magnesium. Calcium is best suited between 400 and 450 ppm, while magnesium can vary from 1250 to 1500 with little noticeable difference.
Some popular Acropora species include:
