How to Create Fake Live Rock

Adding man-made creations to a saltwater aquarium can negatively affect the aquarium's overall health. Anything that throws off the water's pH balance or salt levels can take weeks to fix and could possibly harm the fish. Using the appropriate materials to create fake live rock will not only create new homes for salt water creatures, but can also help the spread of coral.

Things You'll Need

  • Aragonite gravel
  • Portland cement
  • Styrofoam block
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Instructions

    • 1

      Carve the shape of the desired fake live rock into the styrofoam block. Use this as a mold to create the rock.

    • 2

      Mix together one part Portland cement, one part aragonite gravel and two parts water, making aragocrete. This will help coral to attach onto the rock later. Don't worry about air bubbles when pouring the concrete mixture. The porous areas that result from air bubbles will help the spread of coral.

    • 3

      Add water into the aragocrete mixture until it's damp. The mixture should not look muddy.

    • 4

      Place the aragocrete mixture with water into the styrofoam mold. Do not flatten any of the areas, as rocks naturally have bumps on them.

    • 5

      Place the fake live rock mold in sunlight for up to 24 hours before removing it from the styrofoam. The fake live rock can now be placed in a saltwater bath for a week before being introduced to the actual aquarium.