deweaver@surfcity.net

Present Position: Owner/President of Scientific Hatcheries

B.S. in Engineering from UCLA, 1962

M.S. in Applied Science from Univ. of Calif. at Davis, 1966

Ph.D. in Applied Science from Univ. of Calif. at Davis, 1971

Professional Engineer License, CA 1973

California Aquaculture Association

Aquaculture Engineering Society

World Aquaculture Society

American Association for the Advancement of Science

American Fisheries Society

Aquacultural Engineering Journal; editorial Board Member

"Oceans Resources Enhancement Advisory Panel" member - CAA representative

WRAC industrial advisory committee

Aquaculture Disease Committee, State of California; Chairman

In 1973, Dr. Weaver began designing and building closed aquaculture systems with the intent of creating the technology necessary to build a business competitive with existing Asian tropical fish producers (low technology, high labor, pond-based aquaculture systems). The resulting business, Scientific Hatcheries, has evolved from a part-time backyard business to a full-time expanding business, which produces and sells about 20,000,000 fish per year into the tropical fish and research markets. These highly automated hatcheries utilize very high intensity closed systems, which operate with a very low amount of makeup water (high cumulative feed burden - CFB- systems). These facilities have recently been sold and the effort of Scientific Hatcheries is now focused on consulting in aquaculture and liquid waste treatment areas.

As part of the above business, Dr. Weaver has been conducting research on water treatment systems for aquaculture for the last 24 years. The present design approaches have proven to be stable and operable over decade time scales. Dr. Weaver conducted the original research and development on Fluidized Bed Biofilters in 1973 and has been refining the designs, eliminating instabilities and operational problems since 1973. This research has been utilized internally by Scientific Hatcheries and has not been published.

Dr. Weaver undertakes occasional consulting assignments in the aquaculture areas, which he finds interesting or state-of-the-art. These consulting assignments include water treatment system for fish and shrimp hatcheries, maturation systems and broodstock growout systems. All of the systems designed for several clients meet or exceeded design specifications at full loading.

The practical experience of managing and operating systems that Dr. Weaver has designed provides a valuable feedback for improved designs and fewer "built-in problem areas" for future designs.

All Scientific Hatcheries production systems were designed in-house by Dr. Weaver. Scientific Hatcheries is presently operating treatment systems processing about 7,200 l/min with salinities ranging from < 50 ppm to full strength seawater. These are highly automated systems. The last set of 7 systems have operated in a commercial mode for 13 years without any fish loss from system failure problems, only losses from husbandry failures. This high reliability for RAS (recirculating aquaculture systems) was made possible by attention to the design details and conducting failure analysis.

Designed, built and installed water treatment systems for major customers of Scientific Hatcheries live fish products. Designed several major production systems for other tropical fish producers. These systems are all still operating after 20 years with only minor maintenance.

Consulting projects include retrofitting biofilters (whose original design had failed three times during its first year of operation) in the world’s largest closed cycle sturgeon facility to a fluidized bed design that has been operating continuously for over 25 years.

Designed and built systems for two fresh water prawn PL production facilities, which allowed the PL hatcheries to be located independent from a source of salt water. In both of these facilities, multiple batches of PL’s were produced without changing the water.

Designed the biofilter system for the "Freshwater Institute" in West Virginia. This system operates with trout at low temperature and demonstrates the capability of Dr. Weaver’s designs to operate at low temperature with high loading.

Designed and specified the recycle water treatment system for a major SPF shrimp broodstock growout facility. The shrimp hatchery associated with this broodstock facility experienced contamination of its input water well. A retrofit of the well water treatment system corrected the problem and eliminated water quality associated production problems on this 150 million PL per month hatchery.

Specified equipment and aided in the design of six closed cycle shrimp maturation systems (six different clients in four countries). In all four cases, input water quality or temperature problems arose during parts of the year. As a result of Dr. Weaver’s assistance, the closed systems now enable year around operation.

Designed the water treatment systems for a major shrimp hatchery in Central America, which had a significant problem with input water quality (very high ammonia levels).

Of equal importance to the above successful projects are the many clients who were persuaded to abandon proposed projects, which would not have proven to be financially viable.

In general, Scientific Hatcheries does not publish its internal research results. Several oral presentations have been presented at various aquaculture meetings ranging from highly technical (The Impacts of Fish Feed on Oxygen Transport Coefficients) to general closed systems overviews. Dr. Weaver has publish journal articles, studies, reports, etc. in other technical areas not relevant to aquaculture, hence not included in this resume.

Performance information on the fluidized bed biofilters used by Scientific Hatcheries can be found in:

Dallas E. Weaver, "Performance of Fine Sand Fluidized Bed Biological Filters", in Workshop on Design of High Density Recirculating Aquaculture Systems, Louisiana State University