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Hard Coral

Hard Coral

includes brain corals, montipora, acropora, bubble corals, frog spawn and torch corals

"Stony" or "hard" corals have a hard calcium carbonate skeleton. They are a popular saltwater invertebrate for aquariums because of their beautiful colors and unique appearance. Corals are a popular addition to any reef system. Not recommended for beginning marine aquarists.

Hard Coral

Hard Coral Facts

Average Adult Size depends on species, feeding habits and age
Average Life Span depends on species
Diet photosynthetic and/or filter feeders
Minimum Aquarium Size 29-50+ gallons, depending on species
Water Temperature: 72-78°F
Specific Gravity 1.023-1.025


A well-balanced Hard Coral diet consists of:

  • Some corals contain photosynthetic algae in their bodies called "zooxanthellae" which help provide most of their nutritional needs.
  • Liquid or powdered coral diet.
  • Mysis shrimp, brine shrimp, krill or microplankton can be fed to some species.
  • Supplements such as calcium and strontium should be added weekly.


Things to remember when feeding your Hard Coral:

  • Feed tiny bits of brine shrimp, mysis shrimp or micro-plankton once or twice a week.
  • Naturally feed at night.


  • Keep in an appropriate size aquarium; full spectrum, high intensity lighting (T5 is recommended) and strong filtration are essential.
  • Use of copper-based medications is toxic to invertebrates.
  • Stable water quality, water temperature, and pH levels are critical to the health of the invertebrate. If you are unsure of your water quality or pH levels, Petco provides free water testing.

Normal Behavior

  • Large stony polyp corals consist of a calcium skeleton with large fleshy polyps.
  • Some hard corals require increased lighting, filtration and strong, intermittent water flow.
  • Short polyp stony corals consist of a calcium skeleton with numerous small polyps.

Habitat Maintenance

  • Daily: Check filter, water temperature, specific gravity and other equipment.
  • Weekly: Check water quality at least once a week.
  • Monthly: Change 10 to 25% of the total volume of water every 2 to 4 weeks, or as needed.
  • Provide stable decor or rocks for attachment by sessile corals


  • Some Hard Corals can injure others and must be kept segregated.
  • Some aquatic life may feed on coral polyps.
  • Check Petco's Marine Compatibility Care Sheet for more information regarding your specific species.


Signs of a Healthy Hard Coral

  • Bright, even coloring
  • Extended polyps
  • Free of pests

Avoid overcrowded conditions; they are a major cause of stress and disease. Maintain good water quality with regular water changes and adequate filtration.

Red Flags

  • loss of color
  • tissue deterioration
  • polyps retracted for extended periods of time

Common Health Issues

Health Issue Symptoms or Causes Suggested Action
Health Issue Body or surface erosion Symptoms or Causes Poor water quality; nutrient deficiency Suggested Action Test and treat water immediately; maintain proper diet.


Ask an associate about Petco's selection of books on Hard Corals and the variety of Petco Brand products available for the care and happiness of your new pet. All Petco Brand products carry a 100% money-back guarantee.

Because all aquatic life are potential carriers of infectious diseases, such as Salmonella, always wash your hands before and after handling your aquatic life and/or habitat contents to help prevent the potential spread of diseases.

Pregnant women, children under the age of 5 and people with weakened immune systems should contact their physician before purchasing and/or caring for aquatic life and should consider not having aquatic life as a pet.

Go to the Centers for Disease Control at for more information about aquatic life and disease.

This care sheet can cover the needs of other species.

Note: The information on this Care Sheet is not a substitute for veterinary care. If you need additional information, please refer to the sources on the following page or contact your veterinarian as appropriate.

Developed with and approved by a qualified veterinarian.