This model is concerned with simulating a tank containing Talapia. The main focus will be dynamic modelling of the oxygen content of the aquarium. A constant temperature throughout the tank is assumed. 

The setup:

In this simulation we have one aquarium which receives water at a set rate and loses water via overflow at the same rate. At the starting conditions the water is assumed to be in equilibrium with the atmosphere with concern to oxygen. This aquarium can be occupied by any number of fish. All fish start at a average weight of 3.8g.

Fish respiration:

While these fish are in the tank they respire at a certain rate which is dependent on the temperature, the weight of the fish and the current concentration of oxygen. This rate will primarily be limited by physiological factors and by oxygen concentration. The rate of respiration when in oxygen saturated water is considered the maximum rate of respiration. At a certain level of oxygen saturation (i.e. [oxygen tension/atmosperic] partial pressure of oxygen or [O2]/ the Oxygen solubility) the fish will begin to down regulate their activity to compensate for the low oxygen content. This saturation level will be denoted as the oxygen threshold. A final threshold is the oxygen level of no excess activity, which is also temperature dependent and below which the fish will do nothing but what is needed the just survive. This respiration rate is set to be 0.1 times their maximum respiration.  Both the respiration, the oxygen level of no excess activity and the oxygen threshold are calculated from data of Fry and Hart 1948 and are temperature dependent. 

Fish Growth:

The fish grow at a set rate of 26.4 g/mol(O2) assuming a assimilation rate of 1 part C  pr. part O2 respired. The more the fish grow, the higher the respiration and the faster the growth. If the oxygen level is below the level of no excess activity the growth is set to be 0.

Result: 

The temperature dependent oxygen consumption through respiration is found to follow a power relationship with the following equation: 

18.493*temperature^1.7926 µmol/kg/h

The Km was found to depend on temperature following a power relation with the following equation:

[(0.0393*temperature^0.5472 )*Oxygen solubility]/2 µM
which by insertion of appropriate values at 15 degrees C gives km = 27.67

The level of no excess activity was found as a oxygen saturation adhering to the following power relation:

0.0055*temperature^0.9436 *Oxygen solubility µM

To fit the graph to figure 3 of Fry and Hart I adjusted the biomass of fish until a satisfying result was reached at 190g. 

This model is concerned with simulating a tank containing Talapia. The main focus will be dynamic modelling of the oxygen content of the aquarium. A constant temperature throughout the tank is assumed. 

The setup:

In this simulation we have one aquarium which receives water at a set rate and loses water via overflow at the same rate. At the starting conditions the water is assumed to be in equilibrium with the atmosphere with concern to oxygen. This aquarium can be occupied by any number of fish. All fish start at a average weight of 3.8g.

Fish respiration:

While these fish are in the tank they respire at a certain rate which is dependent on the temperature, the weight of the fish and the current concentration of oxygen. This rate will primarily be limited by physiological factors and by oxygen concentration. The rate of respiration when in oxygen saturated water is considered the maximum rate of respiration. At a certain level of oxygen saturation (i.e. [oxygen tension/atmosperic] partial pressure of oxygen or [O2]/ the Oxygen solubility) the fish will begin to down regulate their activity to compensate for the low oxygen content. This saturation level will be denoted as the oxygen threshold. A final threshold is the oxygen level of no excess activity, which is also temperature dependent and below which the fish will do nothing but what is needed the just survive. This respiration rate is set to be 0.1 times their maximum respiration.  Both the respiration, the oxygen level of no excess activity and the oxygen threshold are calculated from data of Fry and Hart 1948 and are temperature dependent. 

Fish Growth:

The fish grow at a set rate of 26.4 g/mol(O2) assuming a assimilation rate of 1 part C  pr. part O2 respired. The more the fish grow, the higher the respiration and the faster the growth. If the oxygen level is below the level of no excess activity the growth is set to be 0.

Result: 

The temperature dependent oxygen consumption through respiration is found to follow a power relationship with the following equation: 

18.493*temperature^1.7926 µmol/kg/h

The Km was found to depend on temperature following a power relation with the following equation:

[(0.0393*temperature^0.5472 )*Oxygen solubility]/2 µM
which by insertion of appropriate values at 15 degrees C gives km = 27.67

The level of no excess activity was found as a oxygen saturation adhering to the following power relation:

0.0055*temperature^0.9436 *Oxygen solubility µM

To fit the graph to figure 3 of Fry and Hart I adjusted the biomass of fish until a satisfying result was reached at 190g. 

This model is concerned with simulating a tank containing Talapia. The main focus will be dynamic modelling of the oxygen content of the aquarium. A constant temperature throughout the tank is assumed. 

The setup:

In this simulation we have one aquarium which receives water at a set rate and loses water via overflow at the same rate. At the starting conditions the water is assumed to be in equilibrium with the atmosphere with concern to oxygen. This aquarium can be occupied by any number of fish. All fish start at a average weight of 3.8g.

Fish respiration:

While these fish are in the tank they respire at a certain rate which is dependent on the temperature, the weight of the fish and the current concentration of oxygen. This rate will primarily be limited by physiological factors and by oxygen concentration. The rate of respiration when in oxygen saturated water is considered the maximum rate of respiration. At a certain level of oxygen saturation (i.e. [oxygen tension/atmosperic] partial pressure of oxygen or [O2]/ the Oxygen solubility) the fish will begin to down regulate their activity to compensate for the low oxygen content. This saturation level will be denoted as the oxygen threshold. A final threshold is the oxygen level of no excess activity, which is also temperature dependent and below which the fish will do nothing but what is needed the just survive. This respiration rate is set to be 0.1 times their maximum respiration.  Both the respiration, the oxygen level of no excess activity and the oxygen threshold are calculated from data of Fry and Hart 1948 and are temperature dependent. 

Fish Growth:

The fish grow at a set rate of 26.4 g/mol(O2) assuming a assimilation rate of 1 part C  pr. part O2 respired. The more the fish grow, the higher the respiration and the faster the growth. If the oxygen level is below the level of no excess activity the growth is set to be 0.

Result: 

The temperature dependent oxygen consumption through respiration is found to follow a power relationship with the following equation: 

18.493*temperature^1.7926 µmol/kg/h

The Km was found to depend on temperature following a power relation with the following equation:

[(0.0393*temperature^0.5472 )*Oxygen solubility]/2 µM
which by insertion of appropriate values at 15 degrees C gives km = 27.67

The level of no excess activity was found as a oxygen saturation adhering to the following power relation:

0.0055*temperature^0.9436 *Oxygen solubility µM

To fit the graph to figure 3 of Fry and Hart I adjusted the biomass of fish until a satisfying result was reached at 190g.