How to Keep Water in Small Fish Tanks Clean

Aquariums of all sizes become dirty in time for one simple reason: fish swim in their own toilet. The only way to keep the water clean is by either removing the excrement, or changing the water, which can be a time consuming hassle. This cannot be avoided, but it can be delayed and the hassle minimized with an investment of some time and a little money.

Things You'll Need

  • Power filter with disposable filter cartridges
  • Siphon tube with bulb
  • Bucket or pail
  • Water (at least a single 1-gallon jug, stored at room temperature)
  • Chemical agent to remove chlorine and ammonia
  • One algae eating fish (plecostomus)
  • Clumping agent
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Instructions

  1. Small Fish Tank Maintenance

    • 1

      Place a power filter in your aquarium if it does not already have one. If you have a power filter, replace the disposable cartridge every three to four weeks, or when the water becomes cloudy or smells foul.

    • 2

      Change 20 percent of the water from the bottom of the tank (where excrement gathers) once a week; use a siphon tube with a bulb to avoid the nasty surprise of an accidental mouthful of filthy aquarium water. Place a bucket beside the fish tank, lower than the tank. Insert the bulb end of the siphon into the bucket and the far end into the aquarium. Squeeze the bulb to begin the flow, and then rake the far end of the tube over the gravel on the bottom of the tank, stirring up the excrement and sucking it out of the tank. Stop when about 20 percent of the water has drained, or what is required to remove as much waste as possible; remove the far end of the tube from the tank (be careful not to suck up any small fish, such as young tetras).

    • 3

      Use water stored at room temperature in gallon jugs that has been treated with a chemical agent to remove chlorine and ammonia to replace the water removed from the tank. Use the siphon to transport the clean water into the tank to avoid splashing, disturbing the stones and plants or upsetting the fish.

    • 4

      Place an algae-eater in the tank if green scum (algae) starts building up on the glass. Exposing the aquarium to sunlight promotes algae growth. The plecostomus should keep the glass clean; if the tank is too large for a single plecostomus to remove all algae, place another one inside.

    • 5

      Add a clumping agent to the water to encourage small particles (excrement) to stick together, reducing cloudiness, if the problem persists. Clean your filter after one hour, as the use of clumping agents will often clog up filters. The waste will still need to be removed regularly.