Aquaculture Systems Technologies, LLC (AST) was founded by Douglas Drennan, in October 1995, as a direct result of the acquisition of Armant Aquaculture, Inc. (AAI). AST acquired from AAI certain assets including, but not limited to, the exclusive manufacturing, marketing and sales rights for "Propeller-Washed Bead Filters" and similar non-exclusive rights for the "Bubble-Washed Bead Filters". Both filter configurations are patented, and AST has an exclusive licensing arrangement with the patent holder. Shortly after completing the acquisition, Douglas set about refining the complete line of propeller-washed bead filters which his new company would offer, doubling the number of filter models available from three units (PBF-8, PBF-20 and PBF-30) to six units (PBF-3, PBF-5, PBF-10, PBF-25, PBF-50 and PBF-100) and improving the design by increasing pressure tolerances from 15 psi to 20 psi on all of the fiberglass units, installing FRP coupling in place of bulkhead fitting for the inlet/sludge outlet on the side of the filters and using mechanical seals in place of packing on the filter head where the shaft penetrates the filter hull.
Today, AST’s product line features ten propeller-washed bead filter models with bead capacities ranging from 3 ft3 to 100 ft3 and seven bubble-washed bead filter models with bead capacities from 1/4 ft3 to 10 ft3 . These filters are often referred to as bioclarifiers for their ability to perform both biological and mechanical filtration in a single unit. Bead filters operate very much like submerged rock beds or undergravel filters, with the added advantage of easy cleaning.
Bead filters are generally classified as expandable granular biofilters and are distinguished by the use of buoyant granular media. The packed bed of plastic beads, through which water from the tank passes, captures solid waste (100% of particles >50 microns and 48% of particles 10-50 microns). Simultaneously the beads provide 400 ft2 / ft3 of surface area for the attachment of nitrifying bacteria, which metabolize dissolved nitrogenous waste.
AST also offers seven proprietary bead filter controllers, which automate filter backwashing. The controllers contain a programmable microcomputer and a central processing unit with random-access and read-only memory devices. All controllers offer a choice of 16 preset backwash frequencies. Additionally, the propeller-washed filter controller has 16 settings to control the duration of propeller mixing and 16 settings to control the sludge drain time.
Although the core of our business is the manufacture and sale of bead filters, AST is continually working to develop new products to improve recirculating aquaculture technology. See R&D for more information on products and technologies currently under development.
Located in New Orleans, LA, at 108 Industrial Ave., AST currently occupies a 5,200 square foot building which is divided into approximately 800 square feet of office space, and 4,800 square feet of warehouse space. Two 30' x 60' greenhouse occupy the rear two-thirds of the property. The first green house contains three freestanding 1,800 gallon recirculating systems. Each system is currently equipped with a fully automated Model PBF-3 bead filter for biofiltration and solids capture, a ½ Hp centrifugal pump, an automatic feeder, and a submersible heater. Four 900 gallon saltwater systems are also located in this greenhouse. Each of these systems is currently equipped with a fully automated Model MRBF-1.5 ft3 airlift bead filter for biofiltration and capturing solids, an automatic feeder, and submersible heater. The second greenhouse is being used to house a HISTAR system (Hydraulically Integrated Serial Turbidostat Algal Reactor System). Two 2.5 HP regenerative blowers provide aeration to all three systems and--in case of a power failure--a 5 kW back-up generator is available.
AST also has a water quality laboratory equipped with a dissolved oxygen meter, pH meter with probe, two digital scales, turbidity meter and a temperature compensated refractometer. Our latest addition is a spectrophotometer. This instrument is capable of running over 120 different water quality parameter tests, with many of them to US-EPA standards. AST has the additional ability to perform several sophisticated tests as outlined in Standard Methods (APHA, 1995) for dissolved oxygen, carbon dioxide and alkalinity. A 10X-1000x microscope has recently been purchased for work with algae, zooplankton and any fish disease problems that might arise.