9.4 Aquaculture Wastewater Recycling
Aquaculture activity requires huge quantities of water with an adequate physicochemical quality (Alatorre-Jácome et al. 2011). Research in Amazcala campus,
from the Universidad Autónoma de Querétaro, shows that is possible to have fish
production with a low waste of water at least with Tilapia (Soto-Zarazúa et al.
2010). To solve water quality problems, various systems for replacement, filtration
and recirculation of water have been proposed in various scientific studies
(Piedrahita 2003; Shnel et al. 2002; van Rijn et al. 2006). In these systems,
mechanical and biological clarification and ultraviolet sterilization processes were
applied in different configurations to keep the water properties within the
acceptable ranges for fish survival and growth. Regarding dissolved oxygen, some
controllers have been developed (Bergheim et al. 2005). On the other hand, fish
behavior has been analyzed to evaluate the optimal ranges for fish production (Xu
et al. 2006). A recirculation system has been tested in order to probe the time for
water exchange. Results showed that the system allows keeping recirculation water
during 4 months with desirable physicochemical parameters. This fact represents a
significant saving for farmers and environment. Even more, when the water is
delivering from the system could be used in other systems such as aquaponics,
microalgae culture, lombriculture among others (Rico-García et al. 2009).
9.5 Control and Environment for Aquaculture
In recent years, consumers around the world have increased the consumption of
fish due to the recognition of their nutritional value (Tingman et al. 2010); for this
reason, intensive aquaculture aims to increase fish production capacity per cubic
meter of water. However, when fish densities are large, the influence of temperature, dissolved oxygen and water quality on fish survival, and growing rates
increases. Aquaculture facilities therefore require an automated method of keeping
these parameters within acceptable ranges to optimize their efficiency by reducing
labor and operational costs (Avnimelech 2006); when these parameters are outside
of the optimal ranges, stress and slow fish growth is fostered, which has a direct
effect on quality, quantity, and harvest time. According to Burel et al. (1996), the
control of these factors is complicated, and they can only be monitored and kept
within tolerable ranges.
Fish culture facilities inside greenhouses represent an important alternative
method of maintaining water temperatures within the acceptable range for fish
survival. Thereby obtaining high growth rates with low feed conversion rates, due to
the effect of temperature on fish metabolism and consequently on food consumption.
However, the temperature control can be improved by the design of new strategies
for water distribution among the tanks, taking into account the tanks’ position inside
the greenhouse and the temperature effect of air and soil on the water.
9 Aquatic Biosystems
281
Aquaculture activity requires huge quantities of water with an adequate physicochemical quality (Alatorre-Jácome et al. 2011). Research in Amazcala campus,
from the Universidad Autónoma de Querétaro, shows that is possible to have fish
production with a low waste of water at least with Tilapia (Soto-Zarazúa et al.
2010). To solve water quality problems, various systems for replacement, filtration
and recirculation of water have been proposed in various scientific studies
(Piedrahita 2003; Shnel et al. 2002; van Rijn et al. 2006). In these systems,
mechanical and biological clarification and ultraviolet sterilization processes were
applied in different configurations to keep the water properties within the
acceptable ranges for fish survival and growth. Regarding dissolved oxygen, some
controllers have been developed (Bergheim et al. 2005). On the other hand, fish
behavior has been analyzed to evaluate the optimal ranges for fish production (Xu
et al. 2006). A recirculation system has been tested in order to probe the time for
water exchange. Results showed that the system allows keeping recirculation water
during 4 months with desirable physicochemical parameters. This fact represents a
significant saving for farmers and environment. Even more, when the water is
delivering from the system could be used in other systems such as aquaponics,
microalgae culture, lombriculture among others (Rico-García et al. 2009).
9.5 Control and Environment for Aquaculture
In recent years, consumers around the world have increased the consumption of
fish due to the recognition of their nutritional value (Tingman et al. 2010); for this
reason, intensive aquaculture aims to increase fish production capacity per cubic
meter of water. However, when fish densities are large, the influence of temperature, dissolved oxygen and water quality on fish survival, and growing rates
increases. Aquaculture facilities therefore require an automated method of keeping
these parameters within acceptable ranges to optimize their efficiency by reducing
labor and operational costs (Avnimelech 2006); when these parameters are outside
of the optimal ranges, stress and slow fish growth is fostered, which has a direct
effect on quality, quantity, and harvest time. According to Burel et al. (1996), the
control of these factors is complicated, and they can only be monitored and kept
within tolerable ranges.
Fish culture facilities inside greenhouses represent an important alternative
method of maintaining water temperatures within the acceptable range for fish
survival. Thereby obtaining high growth rates with low feed conversion rates, due to
the effect of temperature on fish metabolism and consequently on food consumption.
However, the temperature control can be improved by the design of new strategies
for water distribution among the tanks, taking into account the tanks’ position inside
the greenhouse and the temperature effect of air and soil on the water.
9 Aquatic Biosystems
281