How to Make My Frag Grow

Written by rachel spradling
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How to Make My Frag Grow
Populate your reef aquarium with coral frags. (Jupiterimages/ Images)

Corals have been living in Earth's oceans for 230 million years; sadly, coral reefs are currently disappearing worldwide. Saltwater aquarium hobbyists are helping to preserve reefs by buying coral fragments, or "frags," when populating home aquariums rather than buying corals pulled from the ocean. Coral frags are corals that have been harvested from existing aquarium corals, not natural reefs. A frag begins as a coral grown in an aquarium. When that coral has grown large enough, a piece is clipped off -- the fragment -- and glued onto a disc, or "plug." Coral frags are living animals and will grow, or "bud," in your aquarium if they have the right tank placement; lighting, water temperature, flow and chemical balance; and food for their species.

Skill level:

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Things you need

  • Water test kit
  • Nylon fishing line
  • Liquid calcium
  • Mysid shrimp, rotifers or phytoplankton

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  1. 1

    Place the new coral frag in the sand at the bottom of the tank to allow it to adjust to your tank's lighting system. Gently handle the coral frag by the base, or the plug. Avoid touching it with your bare hands.

  2. 2

    Determine the coral's permanent spot in the tank according to what species it is; different species of coral have different water flow and lighting needs. Learn how aggressive your particular species of coral is and place it in the tank accordingly. Some corals are very aggressive to other corals and will burn them if they can reach them. Use nylon fishing line to tie the frag to its permanent home so it won't be knocked over by other tank inhabitants.

  3. 3

    Test the tank water with a test kit for water quality on a weekly basis; corals will die if tank chemistry is not appropriate for their species. Test that ammonia and nitrite are at zero; nitrates less than 20; KH (carbonate hardness) at 8 and calcium at 400. Add liquid calcium to the tank on a regular basis to keep the calcium levels at 400; corals need calcium to grow.

  4. 4

    Attach a water temperature gauge to the inside of your aquarium. Check the water temperature daily to ensure it stays between 25.6 to 28.9 degrees Celsius, with no more than a two degree fluctuation per day.

  5. 5

    Feed your corals mysid shrimp, rotifers or phytoplankton, depending on its species, two times per week or every other day.

Tips and warnings

  • Learn about species of coral and their needs before you bring one home. Frags will only grow with proper care.
  • Some of your corals should be large enough to frag after about 18 months.

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