The Green Hydnophora is a stony coral originating from the Indo-Pacific. This particular coral is maricultured by ORA in the Marshall Islands. Instead of being collected from delicate reefs, these corals are grown in aquariums on land using seawater or offshore in a controlled area separate from natural reefs. These corals come with many benefits that we will talk about later.
This coral has a branching and encrusting growth pattern. As it grows more branches, the base will spread and encrust on surrounding rock. The branches are dense and irregular, giving the coral a unique form. The coral has a fluffy appearance with a superb bright green coloration.
It is relatively easy to care for, but there are some specific care requirements that you should know to make it as happy as possible.
First, you must keep the coral away from other corals. This coral will likely sting your other corals if you don’t give it enough space. The Green Hydnophora has a potent sting that kills any coral it touches. Space is important.
To display its beautiful green colors, this coral needs intense lighting. You should provide this coral with around 250 micromoles of PAR. When placing any coral under high light, it is essential to acclimate them first. Start your coral in dimmer, more moderate light and gradually move it into higher light. Acclimating your corals will decrease the risk of bleaching and color loss. You can put Hydnophora corals under moderate lighting, but the color will be less intense.
This coral also does best with moderate to strong flow. Water movement is vital for keeping the coral clean while providing nutrients and essential elements. Ideally, you should provide random water flow to avoid dead spots and to promote proper growth.
Being a stony coral, Hydnophora corals require elevated levels of calcium, alkalinity, and magnesium that are reasonably stable. This coral is less sensitive than Acropora, but more stability with your water chemistry is always better. Depending on how many stony corals you have, you may have to supplement your essential elements using a calcium reactor, two-part dosing, or kalkwasser. These methods work great, but using them properly requires some experience. If you are unfamiliar with supplementing your essential elements, dose in moderation until you become more experienced.
Keep your nitrates around 1-5 ppm and your phosphates as close to 0.01 ppm as possible. This is a safe target range but not a strict rule. Keep your temperature between 72-78 degrees Fahrenheit and stable.
Finally, let’s discuss feeding. Like most corals, this coral contains zooxanthellae, which provide most of the coral’s nutritional needs via photosynthesis. Because of this, the coral doesn’t require feeding. However, feeding you corals can increase coloration, growth rate, and overall health. Feeding your corals is beneficial if you don’t cause nutrient spikes. This coral is a particularly aggressive feeder. It will eat small meaty foods from mysis to powdered coral foods. Dosing phytoplankton and amino acids is a great alternative. This method will keep your corals fed without causing nutrient spikes.
Placement: You can place this coral anywhere with lots of space from other corals as long as you meet its lighting and flow requirements.
Lighting: Medium to high.
Flow: Moderate to strong.
Parameters: 72-78° F, pH 8.1-8.4, salinity 32-35 ppt
Calcium: 350-450 ppm
Alkalinity: 8-12 dKH
Magnesium: 1,250-1,350 ppm
Benefits of mariculture
Maricultured corals such as this Green Hydnophora from ORA are hardier and better able to handle the stress of shipping than coral collected from reefs. These corals are also more sustainable and environmentally friendly. Please do your part to decrease our hobby’s negative impact on the ocean by choosing mariculture and aquaculture.