QUALITY CHECK’ OF WATER

SPORT FISHING LAKES

In recent years the proliferation of facilities dedicated to sport fishing has slowed down rapidly. This phenomenon was caused, as well as the general economic trend for recreational activities, from an ever-growing awareness that, to correctly manage a sport fishing lake, it is not enough to put water and fish into a more or less deep depression and let people fish.

A sport fishing lake has a life of its own and a series of peculiar characteristics depending on its location, of height above sea level, the presence of a natural body of water nearby, in the type and characteristics of the supply water, in depth and morphological parameters, etc.; based on these characteristics it is possible to establish the species to be introduced, both quantitatively and qualitatively, the best fishing systems to use, any treatments to maintain water quality at acceptable levels, turnover times and many other variables that change from situation to situation.

The management of a sport fishing facility, whatever type it is, cannot ignore accurate and constant control of water quality, not only in terms of possible risks for fish fauna, but also and above all in terms of productivity.
Aquaquality was born precisely from the need for a prevention service, diagnosis and treatment of problems related to the quality of the water in which the fish lives.

The inconveniences that occur most frequently, and which generate a series of significant economic problems, first of all the fish deaths, they are the anoxias (lack of oxygen dissolved in water). The latter can be caused by the most disparate reasons but what is important to know is that they can be effectively prevented with correct and careful management of the system and with optimization of the structures present.
However, there are a number of problems, in addition to that of anoxia, which are linked to the quality of the water in the systems: from algal blooms, resulting in decomposition of the organic biomass at the bottom, typical of basins subject to eutrophication, to the possible presence of toxic substances (one of the most common examples is that of ammonia, chemical species produced by the fish themselves through their own excrement, but what, under particular temperature and pH conditions, it is then toxic to their body).

Aquaquality provides a series of services and products ranging from prevention (risk assessments, algal productivity assessments, etc.), to the diagnosis (various types of field and laboratory analyses) and finally to treatment (supply of oxygenators, destratifiers and other machines suitable for improving water quality). Furthermore, the quality of the water in a plant can be assessed not only in terms of risk for fish fauna but with the specific objective of optimizing management and increasing the productivity of the plant itself. (productivity assessments).

QUALITY CHECK’ OF WATER

AQUACULTURE PLANTS

Water quality is of primary importance for the correct management of any aquaculture system.
The plant managers are well aware of this, who dedicate a large part of their activity to this aspect, sometimes without even realizing it.
In fact, fish live in water, and his health (and with it the portfolio of the manager and owner of the plant) depends very strictly on the parameters that affect the quality of the water, first of all the temperature and the concentration of dissolved oxygen.

SUPPLY WATER

The evaluation of the characteristics of the sources (understood as sources of withdrawal in general) of the water entering the system is the first fundamental operation to be carried out for the purposes of a correct overall vision.
The type of source will provide us with radically different problems if the water comes from deep dug wells, from sources that flow from the surface or from water that is taken directly from a body of surface water (lago, river, channel, irrigation or artificial basin in general).
Furthermore, the possible presence of pollutants must be assessed, or in any case of substances that can interfere with the health of fish fauna, e, Consequently, Any treatments to be performed on the water entering the system must be clearly indicated, treatments that often increase management costs, but they are also essential to avoid concrete risks of deaths or other related problems.

SYSTEM WATER

The plant water is probably the section in which the controls and analytical determinations must be more accurate, precise and sensitive, to extensively assess the risk associated with the health of fish fauna. Save and exit
The first operation to be carried out is the determination of all the chemical-physical parameters of interest; naturally the analyzes must be accompanied by a suitable and complete interpretation of the data obtained, also keeping in mind the possible interactions or synergies between correlated values ​​of different parameters (for example, the toxicity of ammonia for fish depends on the pH and temperature of the water at the time of sampling, that of nitrites by the concentration of chlorides, that of heavy metals by hardness, etc.)
The determination of the critical points of the system is then of fundamental importance, of those points where for a variety of reasons, which can be extremely different and unique to each plant, some operations, if conducted incorrectly, they can cause sometimes irreparable consequences for the quality of the water.
In the end, the general assessment must indicate all the measures to be taken for the improvement and control of the plant water quality for the purpose of risk prevention (anossia, intense blooms, states of toxicity towards fish fauna).

WASTE WATER

E’ finally, it is also necessary to consider the quality of the water returned to the environment, and the opportunity to adopt suitable purification systems, to bring the values ​​of the various parameters within the limits imposed by the tables by current legislation (D. Lgs. 152/06); in this context the advantages of SARs are better understood (Recirculating Aquaculture Systems; see specific section).

FIELD AND LABORATORY ANALYSIS

Aquaquality is able to carry out all analyzes, and parameters directly measurable in the plant or on the lake, such as dissolved oxygen or temperature, that the determinations by sampling and laboratory analysis [pH, suspended materials, BOD5, total phosphorus, nitrites, phenols, hydrocarbons, total and non-ionized ammonia, total residual chlorine, surfactants, heavy metals, to mention those provided for by’ Attached 2, Section B, Table 1 / B of D. Lgs. 152/06 (General criteria and methodologies for the detection of qualitative characteristics, for the classification and computation of conformity of surface fresh waters suitable for the life of salmonid and cyprinid fish)] using approved and ISO certified laboratories for total quality.

E’ important, in the case of lakes or basins of appreciable depth, make the water columns (a series of analyzes at different depths), especially the temperature and dissolved oxygen, in order to correctly evaluate any situations of stratification of the basins.

In some cases, and for particular types of systems, it is then necessary to carry out the determinations that evaluate the algal productivity and the risk of having sudden and unwanted blooms; these determinations are carried out with specific methods, such as the light and dark bottle test and the TSI measurement (Trophyc State Index or Trophy State Index).

The analyzes therefore have diagnostic power to indicate the best management strategies, both for aquaculture plants and for sport fishing lakes.