Indicator Corals

Indicator corals are living early warning systems in saltwater aquariums. They react visibly to changes in important water values – often even before measuring devices or tests indicate a deviation. Whether it's their polyp extension, tissue, or coloration: The behavior of these corals can provide you with valuable clues. For example, Caulastrea corals with retracted polyps indicate a low phosphate level, while Montipora corals lose their color intensity when potassium, nitrogen, or calcium are out of balance. Iodine or fluorine fluctuations can also be detected by the reaction of certain SPS species such as Seriatopora or Pocillopora. By carefully monitoring your indicator corals, you can react to changes in the nutrient balance before damage occurs – and thus actively contribute to the health of your entire tank. All corals in this category come from healthy, parasite-free aquaculture – ideal for aquarists who value sustainability and water stability.