AALSO 2018 Abstracts Wednesday
Supplemental Phosphorus and Organic Carbon Supplementation
to Speed Nitrificiation Barrett Christie, The Maritime Aquarium at Norwalk Watch Video (Login required) Full Abstract
Chemical cycling of newly-constructed life support systems (LSS) through the use of ammonium salts or urea is standard practice in the aquarium industry. These artificial sources of nitrogen have long been used to facilitate growth of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in biofilters prior to the introduction of teleost fishes and other aquatic life, though the process has its limitations. All too often the cycling period essential for good water quality and animal health is cut short or otherwise constrained by the rigors of construction schedules, forcing aquarists and operators to expedite these microbiological processes as much as possible. Cycling of nitrite typically is typically more problematic than ammonia as NOB communities develop more slowly than AOB and must compete for space in biofilms. Though the cycling process promotes chemoautotrophic nitrification most species of NOB are facultative organoautotrophs, and as such can utilize organic compounds as the electron donor in nitrification. Supplementation of organic carbon (as sugar or ethanol) in addition to carbonates and bicarbonates has been found to enable NOB to more rapidly oxidize nitrite concentrations during cycling. Additionally, the supplementation of phosphorus (as phosphoric acid) has been used in aquaculture for years to similar effect to ameliorate “phosphate block” in cycling. The effect of each constituent on nitrification is quantified from small-scale trials, and the practical benefit observed from using both techniques in cycling of multiple mid-sized LSS is discussed. Options for sourcing a cost-effective, readily available substrate to provide both phosphorous and organic carbon are also presented. |
Numbers, Spreadsheets and Graphs:
8 Tips to Effectively Record and Present the Things You Do Every Day Kailen Gilde, Georgia Aquarium Watch Video (Login required) Full Abstract
Information is critical to maintaining healthy aquatic environments, and most of the tasks that people in zoological roles perform can be tracked, analyzed, reported and stored. Effectively managing data streamlines workflow, reduces analysis time, reveals trends and optimizes processes. Clear presentation makes information easier to understand, and tailoring presentations to different audiences increases the information’s persuasive ability. This presentation will cover 8 tips on working with and presenting data, with each step illustrated using an example data set from Georgia Aquarium. Topics covered will include properly setting up a spreadsheet for different applications, the practical use of basic statistics and programming, and advanced graphing techniques. Microsoft Excel will be used due to its universality, but the principals covered apply to any platform. No prior knowledge of statistics, programming or data management is required, however a basic understanding of Excel will be assumed. |
Full Abstract
The Oregon Zoo has a wide variety of aquatic exhibits including harbor seals, sea otters, penguins, and elephants all of which have some form of disinfection treatment. Introduction of a chlorine/acid system in conjunction with an ozone generator disinfecting the elephant exhibit brought concerns relating to byproduct formation potential and maximum contamination levels. Haloacetic acids and trihalomethanes were the main concern as exposure levels at or above the MCL could potentially increase the risk of certain cancers. In addition, long term exposure may cause negative effects on the liver, kidney, and reproductive system. Total trihalomethanes and haloacetic acids analysis were performed by TestAmerica. Results were compared to the EPA regulations for human drinking water levels. Tests were sent out during particular events: chlorine treated, ozone treated, chlorine/ozone treated, and post dump and fill. Results indicated that when calcium hypochlorite was used to maintain a concentration of 0.10-0.20 ppm free chlorine, total trihalomethanes were reported to be 0.0020 ppm. Total Haloacetic acids were found to be 0.0052 ppm. Results relating to the use of ozone as a main form of disinfectant reported total trihalomethanes at 0.0013 ppm and haloacetic acids were not detectable. Post dump and fill using city chlorinated water data showed that total trihalomethanes were 0.0013 ppm and total haloacetic acids at a concentration of 0.025 ppm. Data suggest that the use of chlorine as a main form of disinfection elevates total haloacetic acids and trihalomethanes levels compared to the use of strictly ozone disinfection, which displayed the lowest concentrations to date. In addition, strict protocol was incorporated into exhibit care as campus pools are dumped, deep cleaned, and filled on a specific schedule to reduce increasing concentrations of byproducts. Monthly byproduct testing on the elephant exhibit is also now part of the protocol. |
Sand Filters and Beyond: The Future of Life Support Design
Jeffery Keaffaber & Paul Cooley PCA Global Watch Video (Login required) Full Abstract
Sand filters have been the “Go To” mechanical filtration method for aquatic animal life support system designs for the past 40 years. They are simple, cost effective and with the use of filter aids (including using ozone as a micro-flocculent) can produce excellent water clarity. However, with the increased desire to remove or reduce the use of oxidants in the system, a review of alternative treatment methods has been completed with the objective of optimizing the water quality and minimizing the space requirements, water consumption and capital and operational costs. By looking at existing facilities, installing a full-size pilot plants, and providing a mathematical model to extrapolate the data, an optimization of the full-scale systems was developed. This data will be presented. |