Principles of aeration

Journal of the World Aquaculture Society, 2017

Feed‐based production of ictalurid catfish in ponds is the largest aquaculture sector in the USA. Feed has an oxygen demand, and increases carbon dioxide, ammonia nitrogen, and phosphate inputs to ponds. Major sources of oxygen in ponds are phytoplankton photosynthesis and mechanical aeration; the major sink for oxygen is respiration by fish and by microorganisms in the water column and sediment. Dissolved oxygen concentrations decline when respiration exceeds photosynthesis, and the most crucial time for low dissolved oxygen concentration is at night. Mechanical aeration is applied to avoid nighttime dissolved oxygen concentrations from falling below the critical level for catfish of 3 mg/L. Electrically powered paddlewheel aerators are used by most catfish producers. The oxygen‐transfer efficiency of these aerators is known, but calculations of aeration requirement from stocking and feeding rates are not reliable because of variation in phytoplankton abundance and in weather condi...

International Journal of Current Microbiology and Applied Sciences

In any aquaculture plant maintaining dissolve oxygen (DO) level is essential for the better health and survival of the living organisms present in the water body specially fish. DO level can be maintained by aeration process. The general idea behind aeration is to bring the water into intimate contact with the air. Either the water may be discharged into free air or the air may be forced into water. Aeration process also removes light volatile organic compounds, dissolve gases and fix odor, taste etc. in case of drinking water. Some common Apparatus used includes: low cascades, multiple jet fountains throwing water to considerable heights, spray nozzles discharging above the surface of a reservoir, superimposed trays or shelves, submerged perforated pipes, and porous tubes and plates.There are two ways, standard oxygen transfer rate (SOTR) and standard aeration efficiency (SAE) of describing aerator performance. In selection of aerators for aeration in fish culture tank, durability ...

Journal of the Bangladesh Agricultural University, 2017

An experiment was conducted to assess the effect of aeration using blower on growth and production of tilapia (Oreochromis niloticus) in intensive aquaculture system in six (6) earthen ponds at BAU campus, Mymensingh from May to September, 2016. Treatment 1 (T1) with 3 aerated ponds and Treatment 2 (T2) with 3 non-aerated ponds were designed with similar stocking density (300/decimal) of tilapia. Oxygen supply was ensured by blower for 9 hours daily when oxygen depletion occurs in pond water. Fish growth, pond water and soil quality parameters were sampled and assessed. The DO content in the aerated ponds was higher (7.23 mg/l) from the beginning to the end of experiment compared to non-aerated ponds (2.33 mg/l). There were significant differences (p<0.05) of DO content between two treatments at first and last sampling stages. The higher length (15.64±1.56 cm) and weight gain (143.36±39.33 gm), higher SGR (% per day) for tilapia was (2.54±0.00) found in T1 compared to T2 (2.42±0....

Asian Journal of Microbiology, Biotechnology and Environmental Sciences

Pond aeration systems have been developed to sustain vast fish and invertebrate biomass duringthe past decade. These aeration systems are alterations of standard wastewater aeration systems. Aerationperformancetesting has been significant in selecting design features to provide cost-effective yet well-organizedaquaculture pond aerators. Aerators enhance the oxygen requirement for fish growth, and it iscrucially important in the intensive pond stocked with high densities. Dissolved oxygen concentrations havebeen linked to the water quality of the pond, Fish Growth and Survival, Reproduction, Feed utilization andmicroorganisms. Paddlewheel aerators and propeller-aspirator-pumps are probably most widely used.Aerators usually are placed in ponds to provide maximum air circulation in water. This article summarisesthe importance of mechanical aeration of aquaculture ponds for fish farmers.

2005

Fingerlings of Labeo rohita , Cirrhinus mrigala , Hypophthalmichthys molitrix and Ctenopharyngodon idella (average weight 32.0 gram) were cultured in six brick lined (26'x12'x6') ponds for a period of six months. The stocking ratio was 7:4:4:3, respectively and the stocking density of each pond was 2508 fish/acre. Three of the six ponds served as aerated ponds and other three as non-aerated ponds. Aeration was done with the help of 1/3 Hp vertical pump. Fish in each pond were fed with 20% protein diet @ 3% body weight. The ponds were fertilized with cattle manure (@ 500 kg/acre) and chemical fertilizers @ 20:2:0 (N:P:K). Significantly high growth (P<0.0001) and survival of fish (P<0.0001) was observed in aerated ponds as compared to the non-aerated ponds. Pond aeration has resulted in 2095 Kg/acre more fish production with economic benefit of Rs. 144,130.

Journal of Applied Biotechnology, 2014

E3S Web of Conferences, 2020

Considering that in certain papers the aeration processes are confused with the oxygenation processes, a distinction between them must be made. The paper presents modern water aeration and oxygenation installations. The experimental results obtained for the two categories of installations are highlighted. Theoretical and experimental researches aim to increase the concentration of dissolved oxygen in water; this can be done in two ways: I - by introducing atmospheric air into the water; II - by introducing a gaseous mixture consisting of atmospheric air and oxygen. Version II is better, the results being shown in Figure 11.

Transactions of the American Fisheries Society, 1973

Acta Scientiarum. Biological Sciences, 2011

Academia Letters, 2021