How is a fluorescent tube constructed, and what do you have to observe during operation?
fluorescent tubes are widely distributed in the aquarium hobby. They are a standard light source for almost all aquariums.
A fluorescent layer (a so-called 'phosphor'; this is not identical with the chemical element 'phosphorus') covers the inner side of the glass tube. UV irradiation from gas discharge inside the tube stimulates it to emit visible light, while the glass tube does not allow UV to pass (otherwise special protection measures would be necessary!).
Fluorescent tubes are menufactured in different lengths (wattages) and spectral compositions (light colors). They will perform optimally and live long only with temperatures between 20 - 25 °C. At 50 °C, the tube performance will sink to approx. 85 %. Depending on the "care" and daily operation duration, the tube should be replaced after about 1 - 2 years.
Dr. Bodo Schnell