Plants: Easiest, prettiest, most cost effective filters.

Using Plants as the filters in your water garden provide you easy carefree good water quality and a happy beautiful pond. 

Water Garden Bog & Gravel Filtration: Long Term Clear Clean Water.

There are several methods that you can use to create a bog filtration system for your new pond or your existing one. The benefits and purpose of a bog filtration system is to hasten organic decomposition and to allow the greatest intake of nutrients by your bog plants so that nutrients and organic matter are not returned to the pond, but instead, taken up as nutrients by your bog plants—not algae! Mother Nature’s bog filtration system has been around since the beginning of time in marshlands and aquifers. Pond water travelling through a gravel bed through perforated PVC pipe will deposit bacteria and organic matter that will attach itself to the gravel surface itself. Plants that you have chosen for your bog area take up the organic waste and only clean, clear water is returned to your pond. When you place your chosen plants into the bog area, keep existing soil intact but do remove plants from pots.  At this point, your water does not have enough nutrients established to nourish your plants—yet! 

Some tips to keep in mind before you begin building your bog filtration system are as follows:

  1. The greater the surface area of your pond, the greater the surface of your bog filtration will be, a rule of thumb is to build a bog filtration area 10-20% of the size of your water garden pond and 30% the   size of your koi pond.
  2. Only use 3/8” pea gravel, rinse gravel before use, it may temporarily cloud your water but your bog filtration system will ultimately clear it before long.
  3. Cap ends of your perforated piping so that water is forced to flow through the pipes evenly depositing nutrient rich water all along the gravel. Cut slots into PVC pipe with saw or grinder. Slots should be at least 1/3 to half way through the pipe. Place slots facing up. You can also drill holes in the pipe however holes clog more easily and you need to drill many more than you would imagine.
  4. Space piping 2-3’ apart
  5. Dig bog area no deeper than 12” no matter how large the pond surface area
  6. Install pump on opposite side of filtration system
  7. Choose plants that are appropriate for your climate and the amount of sunlight they will receive (AVOID plants that may become invasive!) Most moisture loving plants work well
  8. Plant 1 plant for every square foot of surface in your bog area, remove plants from pots and leave existing soil ON roots)
  9. Establish a pipe layout and a convenient location for your cleanout pipe
  10. Use tubing within the pond itself to minimize leakage
  11. Do not add a filter to your intake pump as it is counterproductive

    Dwarf Sweetflag 'Ogon' and Louisiana Bog Iris in the newly planted creek stream. 

    Suggested plants for your Bog Filter

    Hibiscus Coccineus
    Variegated Water Celery
    Star Grass
    Pond Iris
    Chinese Lizard's Tail
    Louisiana Iris
    Bog Lily
    Corkscrew Rush
    Creeping Jenny
    Dwarf Horsetail Rush
    Dwarf Papyrus
    Dwarf Sweetflag
    Japanese Iris
    Red Stemmed Sagittaria
    Ruby Eye Arrowhead
    Sweet Potato Vine
    Obedient Plant
    Crystal Ball Pennywort
    Black Madrass Dwarf Rice
    Toothache Plant
    Yerba Mansa
    White Rain Lilies
    Siberian Pink Cups

    Avoid using
    Parrots Feather (Invasive)
    Red Stem Thalia
    Thalia Dealbata
    Aquatic Mint (mentha aquatica) - Invasive
    Green Pennywort - Invasive
    Austrailian Feather

    Filtration through gravel and aquatic plants water garden koi pond stream
    Establish Varigated Dwarf Sweetflag (left) Dwarf Yellow Sweetflag 'Ogon' on right soften rock edges and clean water.

    Raised Bog Gravel Filter with Taro Sweetflag Iris Aquatic Plant Filter Water Garden
    Raised Bog Gravel Upflow filter. Dwarf Golden Sweetflag 'Ogon' New Black Taro, cleaning a surrounding koi pond. Crystal clear down to the bottom at Nelson's in TX.