Multiple types of floating treatment wetlands are available.
Three that are most commonly available in the trade include (in alphabetical order):
Each floating treatment wetland has it's benefits and detractions. Choice of a floating wetland types simply depends upon budget, desired appearance, and desire to harvest materials to remove more nutrients from the pond "nutrient" cycle.
Eight-inch thick plastic (recycled, PET) matrix layers bonded with marine foam (polyurethane) comprise the floating island. The foam provides buoyancy and adhesion. Island buoyancy is asjustable. Organic matter is placed on top of the island before plants are seated.
A half-inch thick mat made of a buoyant material that floats on the pond’s surface. Plants growing in special containers are placed in the holes; their roots grow freely in the water to “mine” the water for nutrients and to provide a large surface area for colonizing microorganisms.
A closed cell foam provides buoyancy, a biomatix foam (recycled plastic) provides increased surface area for microbial colonization, and coir inserts permit "pre-growing" so that the modular floating wetland can stay consistently hydrated.