A lighting unit for illuminating a habitat is provided. The lighting unit includes a housing and a light emitter. The operating parameters of the lighting unit may be adjusted to mimic different natural conditions.

An aquarium system includes an aquarium tank arrangement and a light source. The light source has a controllable output of colored light projecting into the aquarium tank arrangement. The light source can provide a cycle of projecting light of at least two different colors.

An aquarium system includes an aquarium tank arrangement and a light source. The light source has a controllable output of colored light projecting into the aquarium tank arrangement. The light source can provide a cycle of projecting light of at least two different colors.

A LIGHTING DEVICE for illuminating an aquarium (100), comprising: a base layer (111, 611); a plurality of lighting elements (111, 112, 113, 212, 213) mounted on the base layer (111, 611) and comprising a first and a second subset (630A) of lighting elements (111, 112, 113, 212, 213) arranged for emitting a first and a second spectrum of light respectively; a light transmission affecting device arranged for affecting the transmission of light from the plurality of lighting elements (111, 112, 113, 212, 213); wherein the light transmission affecting device is arranged for passing (420) at least a part of the light from at least one lighting element (112, 212, 213, 312) of the first subset (112) having the first emitting spectrum and processing (430) the light from at least one lighting element (112, 212, 213, 312) of the second subset (630A) having the second emitting spectrum; wherein the first emitting spectrum comprises white light or a first colored light; wherein the first colored light comprises wavelength in a first range with peak wavelength below (485) 485 nm; and the second emitting spectrum comprises a second colored light; wherein the second colored light comprises wavelength in a second range with a peak wavelength larger than 485 nm.

An aquarium system includes an aquarium tank arrangement and a light source. The light source has a controllable output of colored light projecting into the aquarium tank arrangement. The light source can provide a cycle of projecting light of at least two different colors.

A lighting unit for illuminating a habitat is provided. The lighting unit includes a housing and a light emitter. The operating parameters of the lighting unit may be adjusted to mimic different natural conditions.