How to Clean a Salt Water Aquarium With Mold

Mold in a salt water aquarium is caused by cyanobacteria. This primitive organism is considered to have characteristics of both bacteria and algae. Cyanobacteria can reach plague proportions in a poorly managed salt water aquarium and will cover the gravel and rocks in thick, slimy mats of mainly red and blue-green mold-like growths. Although salt water aquariums with excessive cyanobacteria growths may need to be completely stripped down, this problem organism can be successfully controlled by promptly removing it as it appears.

Things You'll Need

  • Three, 10-gallon plastic buckets
  • Small bottle of dechlorinator
  • 3 lbs. synthetic aquarium salt
  • Small submersible pump
  • Aquarium heater
  • Three old towels
  • 65-gallon aquarium
  • 3-foot-long piece of transparent plastic pipe
  • Garden tap
  • Long-handled net
  • Long plastic aquarium tongs
  • Stiff-bristle brush
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Instructions

    • 1

      Almost fill a 10-gallon plastic bucket with tap water. Add dechlorinator and stir vigorously for a minute.

    • 2

      Add 3 lbs. of synthetic aquarium salt to the 10-gallon bucket. Place a small submersible pump and aquarium heater into the bucket and leave for 24 hours, so that the water can circulate and heat up. Set the thermostat on the aquarium heater for 79 degrees F.

    • 3

      Switch off all aquarium heaters and pumps and turn off the wall plug, on the following day.

    • 4

      Lay a number of old towels on the floor in front of and under the aquarium.

    • 5

      Place the piece of 3-foot-long transparent plastic tubing into the aquarium and hold it in place. Place the opposite end in your mouth and suck powerfully until water moves up the pipe. Remove the pipe from your mouth as soon as water begins to flow into it and place the end into the second 10-gallon bucket.

    • 6

      Move the end of the pipe over the mats of cyanobacteria that are covering the gravel and suck up as much of the cyanobacteria as possible. Do not remove more than 5 gallons of aquarium water in the process.

    • 7

      Rinse your hands under running water, to remove soap residue and natural body oils.

    • 8

      Stir the gravel in the 10-gallon bucket with your hand to loosen and remove the majority of the cyanobacteria that is clinging to the individual particles. Gently tip the water from the 5-gallon bucket into a drain. Be careful not to lose gravel in the process.

    • 9

      Fill a long-handled net with the recently cleaned gravel and place the net carefully into the aquarium. Hold the net just above the aquarium floor and, using the long plastic aquarium tongs, take hold of the bottom of the net and gently tip the gravel out.

    • 10

      Repeat, until all the gravel has been returned to the aquarium.

    • 11

      Drain 5 gallons of aquarium water into the third 10-gallon bucket. Remove the pieces of rock that are most severely coated by the cyanobacteria and place them into this bucket, containing the aquarium water.

    • 12

      Use a new stiff-bristle brush to remove as much of the cyanobacteria as possible from the various pieces of rock. Move the rocks around in the bucket to dislodge all the cyanobacteria and then return the rocks to the aquarium.

    • 13

      Switch off the small submersible pump and heater that are in the 10-gallon bucket of freshly made-up sea water and remove them from the bucket. Pour the water into the aquarium.

    • 14

      Turn on the wall power source and switch on all heaters and pumps in the aquarium.

    • 15

      Remove the wet towels.