Homemade Aquarium Rock Backgrounds

Realistic rock aquarium backgrounds lend a great deal of ambiance to the fish habitat. However, inexpensive backgrounds fail to appear realistic, and realistic backgrounds exceed the budget of most novice fish keepers. Fortunately, you can create a realistic rock aquarium background designed to fit your budget. All you will need are a few basic supplies that you can purchase from your local home and garden store. Consider the native habitat of the fish in your aquarium and design a backdrop that represents their natural surroundings.

Things You'll Need

  • Plexiglas or thick sheet of styrofoam
  • Silicone sealant (aquarium safe)
  • Rocks
  • Gloves
  • Box cutter or razor knife
  • Ventilated work space
  • Wire brush wheel (if using styrofoam)
  • Drill (if using styrofoam)
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Instructions

    • 1

      Select rocks to use in your backdrop. A variety of sizes is best, ranging from flagstone pieces to small pebbles.

    • 2

      Cut a piece of Plexiglas to fit the inside back of your aquarium closely. Make it just slightly smaller to allow the rocks to overlap the edge. Use thick styrofoam sheeting instead of Plexiglas if you prefer more depth. Use a wire brush wheel chucked into a drill to remove some of the thickness of the styrofoam and create a three-dimensional surface.

    • 3

      Apply silicone sealant liberally to a small area of the Plexiglas or styrofoam surface. Cover only the area to which you can add rocks within two to three minutes.

    • 4

      Press rocks into the silicone sealant. Select rocks that closely fit the contours of adjacent rocks, and fill in empty spaces with smaller rocks or aquarium gravel.

    • 5

      Continue to apply sealant and rocks until the large, flat surface of the Plexiglas or styrofoam is covered. Place the rocks so that they overlap the edge very slightly.

    • 6

      Allow the backdrop to dry completely before installing. Add additional sealant to fill gaps between loose stones if needed.

    • 7

      Place the backdrop into the aquarium and gently push it against the back wall. The tight fit and the weight of the rocks should hold it in place.