ADA’s new lighting system Solar RGB has been developed focusing on healthy growth and beautiful appearance of aquatic plants, as it is positioned as a “high color rendering LED lighting system for planted aquarium”. NATURE AQUARIUM NOTES in this issue introduces the special features of Solar RGB that offers the optimal light for Nature Aquarium.
Appearance of Solar RGB lighting unit
Compact size, light weight and simple design was achieved by minimizing parts/accessories other than the light emitting part, radiation fins and cover. The lighting unit can be hung on Solar I Stand, Solar II Stand or Grand Solar Stand.
Light emitting surface and light distribution
The superb light intensity of 21,000lx (30cm beneath LEDs) is achieved with 160 RGB LEDs (power consumption: 130W, luminous flux: 3,000-3,500 lm). The emitted light is distributed widely with a diffuser installed on the light emitting surface. One unit of Solar RGB is designed for use up to W90cm aquarium tank.
■ Challenges in conventional LEDs
For Nature Aquarium to create a beautiful aquascape by growing healthy aquatic plants, NA Lamp (straight-tube fluorescent lamp, metal halide lamp), metal halide lamp NAMH and NAG (green lamp) as well as twin fluorescent lamp NA Lamp Twin have been mainly used. Recently, LED lamp AQUASKY and AQUASKY MOON is becoming the mainstream lighting system for W60cm and small-sized tanks. Each of these lamps has its pros and cons and users can choose the best one for them depending on the tank size/depth and installation method. While more LEDs are used for the light source of aquarium lighting systems as the global trend, the conventional LED aquarium lights had two major challenges. The first change is the brightness of LEDs. In general, the emphasis is placed on only luminous efficacy (lm/W) and it is often advertised as if “LED with high luminous efficacy= bright lighting system”. But here, we must not ignore the numerical trick of “LED’s luminous efficacy becoming higher if less power is used to emit light”. In addition, the light emitted by LED travels more in a straight line. Therefore, the light intensity (lx) is high only immediately beneath the LED while the light intensity around it is significantly low. For these reasons, many lighting systems installed for an aquarium tank do not offer sufficient brightness even though their luminous efficacy (lm/W) and light intensity (lx) on the labeling/specifications are high. AQUASKY and AQUASKY MOON resolved this problem by using more LEDs, but these products can cover only up to W60cm tank. The second challenge is the color issue of white LED. White LED is commonly achieved by combining blue LED with yellow phosphor coating (yellow is the complementary color of blue). When the light from white LED is cast on planted aquarium, the yellow color is emphasized and the green and red colors in the aquarium do not appear vivid in many cases, although the color appearance slightly differs depending on the phosphor coating used. As a solution to these problems, ADA has come up with a new lighting system – Solar RGB using RGB LEDs.
■ Solar RGB creates innovative light
RGB LEDs are capable of producing white light by emitting red (R), green (G) and blue (B) lights separately. Its great feature is to make red, green and blue colors appear livelier and more vivid when compared with conventional types of white LEDs. Unlike conventional types of lamps using a combination of red, green and blue LEDs or equipped with white LEDs together with LEDs of other colors, Solar RGB illuminates LEDs using a totally different system to offer optimum light for the growth and appreciation of aquatic plants. It was generally well-known that RGB LEDs are not suitable for lighting applications and there were no aquatic lighting systems using RGB LEDs in the past. There were two reasons for it – cost and low color rendering index. For the cost, RGB LED needs three circuits for each of red, green and blue LED separately and this results in higher manufacturing costs when compared with white LED that uses only one circuit. In addition, the average of rendering index (Ra) of RGB LEDs is lower due to the lack of hue in the natural colors. The new Solar RGB leverages on the advantages of separate circuits for red, green and blue LEDs to realize an ideal color balance for aquatic plants. Blue light promotes photosynthesis activity of aquatic plants and also has the effect of making water look clear. On the other hand, green and red lights have the effect of bringing out vivid colors of green and red aquatic plants. When these three color LEDs are illuminated at the same time, the illuminated planted-aquarium appears brighter and vivid. Besides these three primary colors, the intermediate colors such as yellow, red-purple and blue-green also appear brilliant under RGB LED and fish also look livelier. Thus, Solar RGB is perfectly suitable for photographing of planted aquaria. Former ADA CEO Takashi Amano developed NA Lamp for more appealing look of aquatic plants under the water and Solar RGB is an extension of it. As for luminance (lx), Solar RGB ensures sufficient brightness by using 160 RGB LEDs (power consumption: 130W) and realizes the light distribution that covers W90cm tank by distributing the light emitted evenly by a diffuser.
■ Innovative product design realizes bright light
Solar RGB is comprised of pendant type lighting unit and electronic ballast which are separately provided. Thanks to the pendant type lighting unit, Solar RGB unit can be installed on a W60cm tank as well as on W90cm. It can also be used for a large-sized tank by installing two units for W120cm tank and three units for W180cm tank. The lighting unit of Solar RGB is slimmer than that of the conventional Solar Series lighting systems, featuring a novel and an innovative shape incorporating a number of radiation fins into a part of the product design. Although the light emitted by LEDs does not carry heat, the LED elements get hot due to thermal resistance if LED is designed to operate with high electrical power to emit brighter light. Higher temperature generally reduces light output of LED and shortens LED’s service life. Therefore, heat dissipation is very important for high-power LEDs. One of the common thermal management approaches is air-cooling using a fan. Nevertheless, Solar RGB adopted fanless style to enable compact size, light weight and simple structure as a priority. It has a large number of radiation fins that provide natural air flow to help prevent temperature rise. The innovative structure of Solar RGB ensures elegant design and outstanding functionality that offers bright light.
Comparison of color appearance between white LED and RGB LED (spectral distribution chart)
The aquascape illuminated by ordinary white LED appears yellowish overall. For the aquascape illuminated by RGB LED, the water looks crystal clear and green and red colors of aquatic plants look very vivid.
Size / Lighting unit: W43×D28×H6.4 (cm), Electronic ballast: W21×D9×H6.5 (cm)
Weight / Lighting unit: 2.6kg, Electronic ballast: 1.5kg
Input voltage / AC100〜240V 50 / 60Hz
Power consumption / 130W
Luminous flux / 3,000〜3,500lm
Illuminance / Around 21,000Lx (Central illuminance at 30cm distance)
Color temperature / Around 9,000〜12,000K (There are variation in color temperature due to the nature of LED)
LED light / 160 (RGB LED)
LED lifetime / Over 30,000 hours (Actual hours may vary depending on usage environment)
Operating temperature range / 0〜35℃
(From Aqua Journal #251)