Donut Corals

Description

All Scolymia species are located in the Atlantic Ocean along the east coast of the Americas between Florida, through the Caribbean sea and Gulf of Mexico, and as far south as Brazil.

Scolymia Corals are Large Polyp Stony (LPS) Corals.

The Scolymia Coral has many names: "Doughnut Coral," "Scoly," "Disk coral," "Artichoke Coral," "Button Coral," etc. 

 Scolymia Corals are round in shape and found in cup, saucer, flat, or dome-shaped variations. 

They usually have a single oral opening present in the center.Some species may have more than one. 

A Scolymia can grow up to 4 inches in diameter.

Scolys come in a variety of patterns and vibrant hues, with some Corals having a combination of multiple colors. 

The most common Scolymia in the hobby right now are the australis species found in the Great Barrier reef of Australia.

They are basically what most people think of when someone mentions a Scoly.

Smooth skin, great color and several different patterns.

The most highly sought after variety of these Corals is what is termed a “Master Scoly.”

There is no real consensus on what Color and pattern combination makes a really nice Scoly a master Scoly, but generally speaking they have four colors or more and often have intricate patterns.

Species are generally distinguished based on differences in septa number, thickness, and orientation.  

Scoly Corals range from brown to bright fluorescent greens, reds, and purples.

Scolymias grow slowly, gaining about a half an inch each year.

Aquarists can expect most Scolymia varieties to reach about five inches across, although some varieties may only grow to two or three inches.

The slow growth rate of these Corals is not well understood, but researchers have proposed that Cyanobacterial mats may inhibit their growth or even cause shrinkage .

These Corals are hardy and their stony structure makes them strong, but the flesh and tentacles of the coral are actually quite fragile.

While not an outwardly aggressive Coral, they need their own personal space. 

At night, stinging sweeper tentacles will emerge from this coral and insure nothing is encroaching on that personal space, so make sure to give your Scolymia Coral enough room to grow and thrive.

Some Scoly Corals are known to exhibit interspecific aggression by attacking both congeneric species and other Corals, causing them to expel their Zooxanthellates.  

Lighting Requirement

Scolymia are not the most light demanding Coral.

They are Photosynthetic but anything around 50-100 PAR is adequate for their health.

There is some variability to the intensity of their colors with changes in light strength, but developing better colors might have more to do with spectrum provided.

Aquarium keepers can experiment with different light spectrums to find something that both works well for their Aquarium setup and lets their Scoly thrive.

Water Flow

Scolymia Coral care includes figuring out how fast the water in the Aquarium should bemoving. Scolymias tend to prefer water that moves slowly.

This lets food drift towards their mouth, but it also encourages waste to move away from the mouth.

These Corals can withstand a medium water flow if the rest of the Aquarium inhabitants prefer that, but a low flow is best.

Most people have them lower in the tank and possibly on the substrate. 

If placing them on rocks, be careful that nothing falls on them or they do not fall down on something else.

When positioning Scolymia, it's often best to tilt them slightly.

This, along with the Water Flow, encourages waste to move away from the Coral.

It also makes it easier to see the coral's mouth, which is not only entertaining but can also help aquarists keep an eye on their Coral's habits.

Water Parameters

As with any stony Coral, Scolymia make use of Calcium, Carbonate, and Magnesium to build their skeletons so it is important to make sure that your water chemistry falls in line with natural sea water levels.

It is good practice to periodically test just to make sure everything is in the ballpark of natural sea water levels.

Scolymias also appreciate it when additional minerals, such as Calcium and Strontium, are added to the Aquarium Water.

This helps them grow more steadily and keeps their structure healthy.

Here are some quick stats about the ideal water chemistry for Scolymia Coral care 

• Hardness: 7,7-11 dkH
• Calcium: 400-450 ppm
• pH: 8.1-8.4
• Salinity: 35 g/L
• Nitrates : 5 and 20 ppm
• Phosphates: 0,05-0,2
• Magnesium: 1200 - 1350
• Strontium: 8 - 10
• Temperature: 73° - 82° F
• Salinity / Specific Gravity: 1.024 - 1.026

Diet / Nutrition

The Scoly Coral has relatively large, fleshy Polyps and will do best if you feed them 2-3 times each week.

Through their Symbiotic relationship with a Photosynthetic Algae, known as Zooxanthellae, they receive many of their nutrients.

They also filter-feed on the Nutrients in the water column.

Scolymias will benefit greatly from frequent feeding.

They can be given meaty foods such as brine Shrimp, Mysis Shrimp, Micro-Plankton, or Krill. Many Scolymias will also often eat prepared Flake or Pellet Foods.

Offering a variety of different foods will help to ensure that the Scolymia Coral is getting a good balance of the Vitamins and Nutrients it needs to thrive.

These Corals can be fed in the evening or at night since this is when they are most actively seeking food.

However, many Corals become used to their keeper's schedules.

In addition, most Scolys don't need to be fed directly, as they're quite good at simply picking food out of the water.

When you see the Coral’s tentacles sticking out, squirt a little bit of the food near the mouth (in the center) and it’ll take care of the rest by itself.

Many Aquarists also suggest turning off or slowing the water movement while feeding so that the Scolymia Corals can more easily grab at passing food.

To maintain good health, Calcium, Strontium, and other Trace Elements should be monitored and added as needed.

Fragging / Propagating

Scolymias, like all Corals, are actually animals, not plants, so many reproduce sexually.

Scolymias do just this—each Coral releases eggs and sperm into the water. The sperm fertilizes the eggs, and new Corals are born.

When two or more Scolymia larvae settle near one another, they usually fuse together to form one complex Coral with distinct genotypes.

Although this could, theoretically, happen in the home Aquarium, these Corals have never successfully reproduced in captivity.

Some Corals also reproduce by creating new Polyps.

These Polyps look like smaller Baby Corals, or buds, that sit next to the parent Coral.

Some Aquarium keepers have reported that their Scolys have budded or have two mouths, which may be a sign of reproduction. However, this is also quite uncommon and is generally up to chance.

Fragging Scolymia isn't usually considered a good idea.

In order to frag, or split, a Scolymia, you would need to cut through a good amount of Coral flesh and hard, calcified structure, which makes the process difficult to begin with.

Cutting into the flesh and stony structure of a Scolymia is challenging and leaves the Coral open to a number of infections.

Most Scolymia Corals that are cut do not survive the process.

In addition, even Scolymias that survive fragging generally don't regain their round shape, which can make feeding difficult for the Coral.