The light spectrum required by aquarium plants is very different from that of a living room or an LED flashlight. It involves photosynthetically active radiation, called PAR (Photosynthetic Active Radiation), and a full spectrum that encompasses ALL spectral ranges of the visible light spectrum. Only by combining these two components has it been possible to produce the perfect light for aquarium plants! Special features of the new JBL LED SOLAR lamps: JBL LED SOLAR lamps are available as replacements for ALL lengths of fluorescent tubes. The basic JBL SOLAR NATUR kit includes a light bar and a remote control for easy and professional operation. The IR remote control allows for the simultaneous control of multiple JBL LED SOLAR systems, as the IR sensors use the same frequency. If this is not desired, the receivers must be placed slightly further apart. Each LED unit can then be controlled individually with the same remote. Saltwater: The JBL LED SOLAR NATUR was originally designed for freshwater aquariums, but it has also proven itself with saltwater enthusiasts, since almost all their corals come from shallow waters where they benefit from full sunlight. When combined with the JBL LED SOLAR EFFECT, the color temperature is 7800 Kelvin. Lengths: The lengths indicated (e.g., 22W = 43.8 cm) are those of the tube to be replaced. Light bar length: 22W/38.3 cm; 24W/49.5 cm; 37W/68.7 cm; 44W/79.5 cm; 57W/99.2 cm; 59W/109.5 cm; 68W/139.5 cm. Length with brackets: 22W/45-70 cm; 24W/55-80 cm; 37 W/75-100 cm; 44 W/85-110 cm; 57 W/105-130 cm; 59 W/115-140 cm; 68 W/145-170 cm. Calculating the light bar length: the stated length, e.g., for 44 W, is 849 mm with adapters to replace tubes. After deducting the adapter lengths (always the same): -50 mm -5 mm = 794 mm, the actual light bar length.