Fluorometer Controlled Apparatus Designed for Long-Duration Algal-Feeding Experiments and Environmental Effect Studies with Mussels
Figure 1
Fluorometer controlled apparatus (FCA). (a) Schematic drawing of automatic recording apparatus for continuous measurement of filtration rate of mussels at constant algal concentration. Biofiltrated seawater is flowing through a well-mixed aquarium with blue mussels, Mytilus edulis, at a constant rate. Water from the aquarium is continuously pumped through a cuvette in the fluorometer monitoring the algal concentration and back again into the aquarium. When the algal concentration decreases below a fixed trigger level, the dosing pump is activated to add algal suspension from a stock. The total volume () of an algal suspension added over time is stored automatically. (b) Circuit scheme of apparatus. Analog output of fluorometer is connected via an A/D converter (12 bit A/D input of the PMD-1208LS USB-based personal measurement device from measurement computing) to a computer. The measured fluorescence of suspended algal cells in the aquarium correlates with a known cell concentration. When the fluorescence comes below a defined lower trigger value Port B0 sends a pulse to the dosing pump and a defined volume of an algal suspension is added into the aquarium.
