Rastas Zoas (Row #5:B)

There are few corals in the hobby as readily identifiable as Rasta Zoas. It was one of the first commercially available specialty morphs and remains popular to this day. No zoa garden is complete without Rasta Zoas. They are instantly recognizable by their bright green, orange and blue colours. They reproduce by budding and, due to this potential for exponential growth, once established a single polyp can grow into a colony quite quickly. Zoas are found in a wide variety of tropical and subtropical ocean environments. However, common morphs with specific trade names such as Rasta Zoas are almost always aquacultured rather than wild collected. This helps to ensure uniformity as well as making them much more likely to be kept successfully in a home aquarium. They are best placed on rock islands on the substrate. This is because, like all corals, they have no “off switch” and will grow continuously. If they are placed on the main rockwork it is possible for them to grow too quickly and take over. Multiple smaller rocks with different coloured zoas can be placed together to form the classic “zoa garden”. Rasta Zoas are fairly tolerant of a variety of lighting conditions but they should not be placed in very high light areas of the tank as this could cause the polyps to stay closed or even for the whole specimen to “melt”. Flow should be moderate, enough to keep the polyps from being covered by
detritus but not so strong that they are blown around aggressively.

For these reasons, zoa rocks are generally placed on the substrate. Like all zoas, Rasta Zoas are photosynthetic, although they respond well to spot feeding. This will increase their growth rate and may improve colouration. Zoas are one of the few corals that prefers more nutrient rich (dirtier) water and may grow faster in tanks with higher nitrate levels. Care must be taken, however, not to raise nitrates too high as this will have a negative impact on other coral species in the tank. Due to their speed of growth, fragging zoas is common but is a bit of an art form. Since they do not have a calcified skeleton that can be cut, polyps must be scraped from the rock and glued to a frag plug or piece of rubble rock. This usually takes a few tries but is fairly easy once mastered. The fragged polyps will soon attach themselves to the plug and begin to grow a new colony. Due to the possibility of the zoas secreting toxins when handled, it is recommended that hobbyists wear gloves and eye protection when fragging zoas.