How to Change the Substrate in a Tropical Aquarium

There are several reasons for changing the substrate in your tropical aquarium. Your substrate might have become unsuitable for your purpose, such as when you want to convert a fish-only tank to a reef or planted aquarium. Different types of aquariums require different types of substrates. Changing the substrate in an aquarium is a big task, so you should do it only when necessary.

Things You'll Need

  • Holding tanks
  • Siphon
  • Small fish net
  • Scrub brush
  • Algae scrubber, plastic scraper or paper towels
  • Aquarium substrate
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Instructions

    • 1

      Prepare a holding tank for your fish while you̵7;re changing the substrate in the aquarium. Siphon half the water from the tropical aquarium to the holding tank. Gently remove the fish from the aquarium and place them into the holding tank using a small fish net.

    • 2

      Remove plants from the tropical aquarium. Place them gently into a second water-filled tank.

    • 3

      Unplug and dismantle lighting, pumps, heaters, mechanical filters and other electrical units on the tropical aquarium. Siphon the rest of the water from the tropical aquarium into a third tank or a bucket and set it aside.

    • 4

      Remove artificial decorations from the tropical aquarium and clean them with hot water and a scrub brush. Scoop out the old substrate.

    • 5

      Clean the sides and bottom of the tropical aquarium using an algae scrubber, plastic scraper and paper towels. Remove all the algae buildup. Don̵7;t use bleach, detergents or soaps to clean the aquarium.

    • 6

      Spread the new substrate on the bottom of the tropical aquarium. Depending on the type of tropical aquarium you have, you can use regular aquarium sand or gravel, aragonite or crushed corals, or vermiculite or laterite.

    • 7

      Pour the water from the third tank or bucket back into the aquarium. Pour the water slowly to avoid disturbing the newly-laid substrate.

    • 8

      Place aquatic plants back into the tropical aquarium, planting them into the substrate carefully. Pour or siphon the water from the plants̵7; holding tank back into the aquarium. Return artificial decorations to the aquarium.

    • 9

      Scoop the fish out of the water in the holding tank using the fish net and gently place them back into the aquarium. Siphon the water from the fish holding tank back into the aquarium. Remount and plug in all electrical units, including your pumps, filters, lights and heaters.