Aquaculture, the farming of fish and aquatic crops such as kelp and algae, is classically done in natural bodies of water. In land-based recirculating aquaculture systems (RAS), however, tanks or raceways contain the farmed species and the water is circulated through a treatment system. Benefits compared to traditional farming in open cages include reduced emissions of nutrients, less risk of i...

1. Current State of Aquaculture and Environment 2. Aquaculture Water Constituents 3. Waste Water Discharge Guidelines for Aquaculture 4. Introduction to Recirculating Aquaculture Systems (RAS) 5. Recirculating Aquaculture System Applications 6. Primary Clarification – Suspended Solids removal 7. Bacterial Processes 7.1 Nitrification 7.1.1 Nitrition 7.1.2 Nitration 7.2 Denitrification 8. Filtrat...

A completely randomized experimental design was conducted to estimate ammonia excretion rate by red tilapia (Oreochromis sp.) during different stages of its growth in recirculating water system units typically designed to meet the experiment purposes. Eight weight groups each containing 75individuals of 20, 30, 40, 60, 80, 120, 180 and 200g average weight were considered as treatments in duplic...

Floating bead filters (FBFs) are expandable granular filters that display a bioclarification behavior similar to sand filters. They function as a physical filtration device (or clarifier) by removing solids, while simultaneously encouraging the growth of bacteria that remove dissolved wastes from the water through biofiltration processes. Presently, there are two classes of FBFs that exist. Hyd...

Efforts to reduce phosphorus concentrations in aquaculture systems have mainly dealt with improving the bioavailability of phosphorus in fish feed. Once released into the culture water, phosphorus is generally left untreated and discharged with the effluent water. In the present study, results are presented on a prototype recirculating treatment system originally designed for removal of organic...

Recent developments in European recirculating aquaculture systems suggest expanding potential for this extremely water-efficient technique. However, the technology still faces challenges due to concerns over economic efficiency and system stability—both essential in minimizing the risk of financially and environmentally expensive failures. One key factor in maintaining stable production conditi...

The efficiency of concentrating poliovirus 1 from distilled water samples was determined by using a recirculating-flow molecular filtration system. The most efficient recoveries were achieved against members with a 10,000 nominal molecular weight limit pretreated with flocculated beef extract. This procedure yielded a mean virus recovery of 67%.