Brentwood Industries
http://www.brentwoodindustries.com/
I began this search by contacting a sales representative in Mexico named Victor M. Solano.
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The hyperlink located bellow leads to a page that has the specifications for the recommended product of interest. They are PVC tube settlers and the recommended size for the Gracias plant is the tubes with a vertical height of 2 ft or 3 ft.
http://www.brentwoodprocess.com/tubesettlers.html
The figure located above is a depiction of a Brentwood tube looking down from above.
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Materials: Polyvinyl Chloride
http://www.healthybuilding.net/pvc/Thornton_Enviro_Impacts_of_PVC.pdf
Shipping and Supply Chain
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