This is a poly flow media. I use the 1 ¼ inch coarse which offers about 360 square feet of surface area per cubic foot of media for biofilm development. Pea gravel gets you about 100 sq. feet of surface area per cu. ft. of gravel. Bio balls has two sizes. The 1 ½ inch diameter provides 125 sq. ft. of surface area per cu. Ft. of media and the 1 in. diameter bio ball yields 160 sq. ft. of surface area. According to the L.S.U. studies on recirculation systems. 400 sq. ft. of surface area can provide enough nitro somonas and nitro-bactre to keep the water safe enough for 25 pounds of fish with light maintenance and 50 pounds of fish with moderate maintenance at a feed rate of 2% of fish body weight per day. Commercial producers achieve 100 pounds or more per 400 sq. ft. at a much higher maintenance level. I’ve been using this unit for 11 years. It is capable of supporting 170 pounds of koi in a 1000 or 2000 gallon water volume. I built my first poly flow filter in a 300 gallon Rubbermaid stock tank in 1994 which supported a maximum of 500 lbs. of fish with moderate maintenance. So for those of you who suffer from the same “OCD eye candy” disease that I have….well, there is hope. If you care to learn a great deal more, try this site.
http://www.aquanic.org/publicat/state/la/la.htm Here is a list of some of informative reading at this site.
Optimizing Nitrification in Bead Filters for Warmwater Recirculating Aquaculture Systems (PDF 458k)
Nitrification in Fluidized Bed Sand Filters for Use in Recirculating Aquaculture Systems (PDF 31k)
Low-Density Media Biofilter of Recirculating Finfish Systems (PDF 717k)
Suspended Solids Control in Recirculating Aquacultural Systems (PDF 992k)
Intensive Finfish Recirculating Systems Overview (PDF 580k)
Biofiltration for Recirculating Finfish Culture Systems (PDF 339k)
Urban Aquaculture for the 21st Century: Using Recirculating Systems (PDF 132k)
Design of High-Density Recirculating Aquaculture Systems (HTML)
Design of Recirculating Systems for Intensive Tilapia Culture (PDF 517k)
Categories of Recirculating Aquaculture Systems (PDF 1220k)
A Feasibility Study of Using Air-Lift Pumps for Aeration, Degasification, and Water Movement in a Recirculating Aquaculture System (PDF 66k)
Water Quality Requirements and Environmental Impacts Recirculating Aquaculture Systems (PDF 1160k
The Bead Filter for Aquaculture Systems (PDF 99k)
Developing Backwash Protocols for Floating Bead Filters: a Model of Solids-Loading and Biofilm-Retention Effects on Nitrification (PDF 656k)
Design and Evaluation of a Commercial-Scale, Paddle-Washed Floating Bead Filter (PDF 742k)
Production, Characteristics, and Modeling of Aquacultural Sludge from a Recirculating Aquacultural System Using an Expandable Granular Biofilter (PDF 655k)
Interim Design Criteria for Warmwater Recirculating Systems Employing Floating Bead Filters and Blown Air (PDF 126K)
Sludge Production from Recirculating Systems Employing Expandable Granular Biofilters (PDF 750k)
Slow Sand Filtration Technologies for the Containment of Non-Indigenous Species in Recirculating Aquaculture Effluents (PDF 768k)
Have fun...Paul
