Reef Aquarium Coral Types

Large Polyp Stony Corals (LPS)

This category of corals gets its name from the corals’ large, fleshy polyps and their ability to lay down a calcareous skeleton. These corals are very prevalent in the reef aquarium industry because of their hardiness and beauty. Brain, Frogspawn, Hammer, Bubble, Fox and Acanthastrea Corals all fall into this category.

LPS corals are very hardy but do require some basics to remain healthy and proliferate. These corals propagate by budding or splitting and, in the right conditions, can do so very often. To lay down a calcareous skeleton, the corals need adequate levels of available calcium. Most reef aquarium experts agree that a calcium level of 400-450ppm is ideal for LPS corals. If the calcium level in the aquarium is too low, the corals will not have enough calcium to properly form their skeletons. If the level is too high, then other essential elements can be “locked up” in the excess calcium and, thus, will not be available to the reef inhabitants.

Lighting for LPS corals should be in the medium to high range and should be a mixture of daylight bulbs (10-20k) and actinics. You should figure on using 3-7 watts per gallon of water for LPS corals. The actinics will cause the corals to phosphoresce, giving an aesthetic benefit as well as causing an increased production of zooxanthellae – the symbiotic eukaryotes which provide food for the corals via photosynthesis. Although LPS corals can be fed small pieces of fish and shrimp, it is not advised since the zooxanthellae will already be producing food for the coral; excess feeding can lead to water quality problems.

Warning: LPS corals can have sweeping tentacles that will extend at night and burn other corals if contact occurs. This burning adaptation helps the coral keep its little piece of the reef clear of competitors for the same food source, mainly light. Ergo, placement is extremely important.