Tag water quality

It is one of the most commonly measured water quality variables in aquaculture, and probably the most misunderstood water quality variable in aquaculture. The pH levels in water have a propensity to change rapidly, but this is a natural phenomenon that often has little consequences and not much can be done to avoid it. 

Attention to pH, a numeric scale used to specify the acid or alkaline condition of an aqueous solution, is very important. Reducing biomass and feeding rates together with phytoplankton control and liming can often keep pH at desirable values. 

Amigos, colegas y ex alumnos del Profesor Claude E. Boyd, Ph.D. de muchos años de la Universidad de Auburn, no esperan que el nativo de Mississippi vaya a reducir su paso, a pesar del callado anuncio de su retiro a principios de este mes. La carrera de investigador del veterano de 50 años ha sido verdaderamente extraordinaria. 

Friends, colleagues and former students of longtime Auburn University Professor Claude E. Boyd, Ph.D., don’t expect the Mississippi native to slow down, despite the quiet announcement of his retirement earlier this month. The 50-year veteran researcher’s career has been truly extraordinary. 

Uneaten or undigested feed and their metabolic byproducts contribute to declines of water quality in aquaculture systems. Accordingly, feed and feeding techniques require continuous review. Reducing overfeeding is an important opportunity for improving feed conversion ratios. 

Zero-exchange biofloc systems allow elevated stocking densities and production, but also require more dissolved oxygen and thorough water circulation. A new type of air injector uses only a centrifugal pump to recirculate water while naturally aspirating ambient air. 

A study found that feed for salmon and trout had higher organic carbon concentrations than did catfish, shrimp and tilapia feeds. Nitrogen and phosphorus concentrations were similar among salmon, trout and shrimp feeds, and higher than those in catfish and tilapia feeds. 

To start a biofilter together with a source of nitrifying bacteria, you must provide the conditions that will encourage the growth of the bacteria. The basic process requires initial preparation of water chemistry, adjustment of alkalinity to support bacterial growth and the addition of ammonia. 

The creation and application of reference tables for acceptable concentration ranges of physical and chemical water quality variables for culture organisms would be challenging due to the differing tolerances found among the many farmed species. 

Acid rain typically does not heavily affect aquaculture operations, and application of agricultural limestone can buffer water against the impacts of acid rain at facilities that use stream water. 

The intrinsic values of better feeds directly affect shrimp growth and performance in a positive way, but because better feeds produce less waste materials in culture systems, they also result in improved water quality that indirectly improves shrimp performance. 

When producers and markets are separated by long distances, economic losses can occur. In a review involving tilapia, water quality was adequate in hauling trucks, although pH levels dropped during transport. 

The authors have achieved good growth using a fishmeal-free diet for the carnivorous marine fish Florida pompano. In studies, they used pompano as a model marine species in a cost/benefit analysis of two extruded diets. 

Greater knowledge of fouling organisms and their settlement can help lead to greater effectiveness for cage net-cleaning machines. If cleaning is done regularly at certain times of the year, biofouling may be easier to remove or kept from settling on nets. 

Oxidants are used in aquaculture as disinfectants or to enhance water quality. Hydrogen peroxide and sodium carbonate peroxyhydrate can be sources of dissolved oxygen in emergency situations where mechanical aeration is not possible.