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(813)744-5519 Aquaculture Sales Total $73 Million in 1993! The Florida Agriculture Statistics Service reports that Florida's aquaculture sales totaled $73 million dollars in 1993, up 35% from the $54 million reported in 1991, and more than double the sales in 1987. Tropical fish production accounted for 64% of the sales, reaching $46.7 million dollars, a 42% increase in the two years since 1991. Egg layers accounted for almost all of the increase, valued at $28.7 million, and live bearers accounted for $18.0 million. Combined imports of tropical fish for resale were up only 3%. Aquatic plants totaled $13.2 million, up from $9.9 in 1991, a 33% increase. Channel Catfish sales dropped dramatically to $0.55 million from $1.96 million in 1991, a 72% decrease. Alligators held steady at $4.43 million, compared to $4.39 million in 1991, less than a 1% change. Oysters dropped to $0.97 million from $1.37 million in 1991, a 29% decrease. Clams rose to $3.66 million, up from the $1.18 million in 1991, a whopping 210% increase! Tilapia sales saw an 82% increase, going from $0.57 million in 1991, to $1.04 million in 1993. Sport and Gamefish sales increased from $0.79 million in 1991, to $1.23 million in 1993, a 56% increase. Other aquatics (freshwater shrimp, crawfish, eels, etc.) declined from $1.43 million in 1991, to $1.24 million in 1993, a 13% decrease. The entire report will be distributed in the very near future, but the above summarizes the highlights. The bottom line is a very strong one, showing that much of the hard work the industry has done in the last two years has been well worth it. It should be noted that the same two year time period was when regulatory issues came to a head on many fronts, and Hurricane Andrew destroyed many of the operations in the Homestead region. Prices have remained fairly constant during the same time period, with some rising slightly, and others falling. To see this kind of growth indicates to me the overall strength of our producers, and their ability to compete in an increasingly difficult climate. This workshop is designed to give those who attend a general knowledge of what's entailed to do your own bacterial diagnosis. A combination of lecture and hands-on laboratory training, we will cover the major bacterial infections of fish, how to properly diagnose them, and perhaps most importantly, how to treat them. Methods for preparing growth media, taking samples from diseased fish, isolating colonies of bacteria, and performing antibiotic sensitivity tests will all be covered. Special emphasis will be placed on proper selection and use of antibiotics for bacterial fish diseases. While it is recommended that you first participate in one of our general fish health management classes, this is not a prerequisite. The workshop is limited to 15 participants, so sign up quick if you want a spot. To enroll, send a check for $40.00 (NO CASH, PLEASE!), made payable to the "Aquaculture Advisory Committee". Mail it, care of me to: Aquaculture Program For more information please contact me ([813]744-5519) or Dr. Ruth Francis-Floyd ([904]392-9617). Recirculating systems are rapidly gaining more attention in aquaculture. Increased pressures on water supplies indicate that new methods are needed to allow for reuse of water whenever possible. In open ponds, fish production is often made difficult due to environmental impacts of weather and other natural forces such as predation from fish eating animals (BIRDS!!). While much information is available in the existing literature concerning the various components of a recirculating system, little attention has been paid to the overall ecology which develops in the system. Hal Simmons has been operating a successful recirculating system for six years. Hal also has a degree in chemical engineering from the University of Florida. He has agreed to share a bit of his knowledge on the chemical and biological aspects of a recirculating system. If you are involved in operating a recirculating system, or anticipating constructing one, I don't anticipate that I could provide a better speaker or format. Total Alkalinity and Liming Total alkalinity is a measure of the total dissolved bases in water. One of the most important groups of bases which will register on a total alkalinity test are the carbonates. Carbonates serve as a buffer for pH in water. When carbon dioxide is produced by respiration in water, it acts as an acid, dropping the pH. When carbonates are present, carbon dioxide enters a "carbonate cycle", and the pH is relatively stable. In a pond with low carbonate levels, carbon dioxide can cause rapid changes in the pH. During the day, carbon dioxide levels in ponds are typically low, or non- existent. Algae in the water use carbon dioxide as quickly as it is produced in the process of photosynthesis. However, at night, or in darkness (rainy days), carbon dioxide levels can quickly be elevated, since even the algae is respiring. In cases with extremely low carbonates, daily fluctuations in pH levels can be severe, causing other problems in the water quality of the pond. Limestone is calcium carbonate, and dolomite is a mixture of calcium and magnesium carbonates. By adding crushed limestone or dolomite to a pond, you can increase the carbonate and total alkalinity of a pond. Total alkalinity levels in a pond should be above 50 parts per million. If you measure the total alkalinity and it is less than 50 parts per million, add crushed limestone or dolomite at a rate of about one ton per surface acre. Buy the finest grade of limestone available, as it will dissolve in the water better than a course grade. Total effect of liming will not be measured for several weeks, as it dissolves slowly into the water column. Spreading the limestone evenly across the pool surface and/or placing it on an elevated platform just below the surface will also help dissolve it. Hydrated lime and quick lime do not contain carbonates. While they will temporarily raise the alkalinity and pH, there is very little buffering provided by either product. As a pond sterilizing agent they are effective, but if your intent is to raise the total alkalinity of the pond, use limestone or dolomite as mentioned. Raising the total alkalinity and carbonate levels provides several benefits:
Total alkalinity is not pH, and is not hardness. They are all closely related and interact with each other in water, but they are separate terms and measurements. It is highly recommended that farms get a handle on the total alkalinity of both their ponds and their water supply systems. If you find that the alkalinity is low, it is easy and inexpensive to raise the levels to a more favorable condition. Bayluscide Unavailable in U.S. In my last newsletter I was trying to help the Florida Tropical Fish Farms Association (FTFFA) get the industry to place orders for Bayluscide. While this was going on, efforts were under way to try and secure a source for Bayluscide for the industry. Unfortunately, as of this date it does not look good. Apparently we will have to wait until next year to order any Bayluscide for Florida. Florida Aquaculture Association (FAA) Annual Conference The FAA has scheduled this year's conference for November 4, 5 and 6, at Harbor Branch Oceanographic Institute in Fort Pierce. This year's conference promises to have a wide variety of educational meetings covering all of the major crops currently in production, plus a few new ones. Registration and agenda information should be distributed in the very near future, but I just wanted to let everyone know the dates. Craig A. Watson |