How to filter aquarium water with sphagnum moss

Written by judith willson Google
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How to filter aquarium water with sphagnum moss
You may use sphagnum peat moss to filter an aquarium. (Jupiterimages/ Images)

Sphagnum peat moss is an alternative filter medium for aquariums. It helps raise the acidity of aquarium water and is effective at filtering out minerals and softening hard water. Sustainably harvested peat moss is now available for aquarists and gardeners concerned about environmental implications. Sphagnum peat moss is potentially renewable as it grows on the surface of peat bogs and will grow back if harvested carefully.

Skill level:
Moderately Easy

Things you need

  • Sphagnum peat moss
  • Phosphate and nitrate test kits

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  1. 1

    Purchase sphagnum peat moss sold specifically for aquarium use, or labelled "organic." Sphagnum peat moss sold in garden centres often contains chemicals that could be extremely dangerous to your fish. Even fertiliser encourages algal blooms.

  2. 2

    Rinse a couple of handfuls of peat moss in distilled water or dechlorinated tap water to remove dust. Dechlorinate water by leaving it in a bucket for at least 24 hours.

  3. 3

    Replace some or all of the filter media in your filter with the peat moss. Remove all the carbon for a blackwater tank, but leave some in if you wish to raise the acidity without the water taking on a brownish hue.

  4. 4

    Change the peat moss more frequently that you would artificial filter media. Two or three times a week is sufficient.

Tips and warnings

  • To ensure the peat moss contains no high levels of nutrients, place two handfuls into two pints of water, leave them overnight, and then test the water to measure phosphate and nitrate levels.

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