Spectrally Tunable Lighting For Aquarium

[lightsource]

I am an Edmontonian who has developed a spectrally tunable light source, and am trying to find out if it may be of interest to those owning aquariums. The light can provide a near perfect match to the intensity and wavelength distribution of the solar spectrum, or instead emphasize parts of the spectrum that may be important for growth of plants or for optimizing the perceived colour of fish. It could cycle day/night or could mimic the spectrum hitting the ocean at any point on the globe (or the underwater spectrum at a prescribed depth).

Currently I am looking at applications to solar cell calibration and botany research. However I know little about the needs of aquarium owners and wonder if this type of lighting is advantageous and whether the instrument should be modified specifically for aquarium use. Thanks for any comments or replies!

[Iceturf]

What form of source is this, doped silicone LED matrix?

Edited March 13, 2016 by Iceturf

[lightsource]

It is a matrix of LED's of different wavelengths, carefully chosen in wavelength, bandwidth, and power in order to provide a precise solar illumination. The device is currently used in solar catalysis work, but I am wondering what features might be desired for aquarium use.

[geleen]

No expert ,here are my thoughts

Planted fresh water tanks have very different needs from saltwater...which need much more light and at Kevin temps 14000 to 20000

Fresh water plants need 6500 K - 5000-7000 K

One useful measurement is the par values as measured at different depths THROUGH water ..every 6 inches to maximum 24 inches. At 24 inches high light plants need say 50-80 par. Lower light plants 30 and up.

Another measurement is the angle of dispersal through water, most used would be 120 degrees or rows of 90 degree for better penetration.

It appears that at the moment the best results are with "Cree" led of up to 3 watts each.

Heat from the lights needs to be dealt with and if using fans, noise is an issue.

Non planted tanks can be served by cheap led's and as long as you penetrate to the bottom your good. 3000-7000K

Plants like the red spectrum so a mix of red and white is common as are some blue led that can be timed for evening viewing so called moon light.

Hope that gives you a start.

Edited March 13, 2016 by geleen

[Psylant]

I built my own LED fixture a few years ago with the help of people on forums. Here's why I built what I did, and probably most other people would agree.

Ideal features for aquarium use...

-Dim each colour of LED in increments of 1% or smaller, all on their own timers so they can be programmed to fade in/out as desired. This is if you wanted to sell controllers... Probably the most requested feature for higher end lighting system though.

-You'd probably need 2 different versions of the light. One for freshwater and one for saltwater corals. Freshwater will be much "warmer" than the saltwater variant as geleen mentioned in the post above.

-Multiple different angled lenses for the LEDs so you can hang the fixture higher or lower as needed to suit your tank and also give better penetration if required. (maybe this could be an "extra" to buy to keep costs low?)

-Splash guard over the LEDs would probably be a good idea for most people. (another extra)

I will think some more and if anything comes to mind I'll post again.

[lightsource]

Geleen & Psylant;

Thanks to both of you for your replies and advice. That gives me a great start and some modification targets to what I've built already.

Many thanks!

[geleen]

I would be interested to learn more about your progression. Also to try the unit(s) perhaps as a trail

John

[Psylant]

I just thought of another thing.

The ability to chain the lighting units together to be controlled all as one unit is another nice feature that some premium quality lights have. Definitely not a "must have" but it's a nice feature nonetheless for people with large tanks. Again, this would probably be more of a controller thing than a lighting thing, but that's what most people are looking for in my experience, is controller features and customizability, along with a full spectrum light which you've already designed from the sounds of things.

[Iceturf]

spectrally tunable light source .... However I know little about the needs of aquarium owners and wonder if this type of lighting is advantageous and whether the instrument should be modified specifically for aquarium use. Thanks for any comments or replies!

Well I think I get the just of what your approach is - you are superimposing known spectral bands on top of eachother to create an 'overall' waveform light coloration. Its a good idea, more efficient than the typical approach of using Phosphorous coatings, which is how most 'white' light is created. The real question here is, will you have more led's on the edge of wavelengths not commonly used by aquarium owners? The only real issue, is perhaps waste, when some or many LED's may get under-ulitilized. Its probably cheaper not to care about underultilization and just go with a single super mass manufactured design.

I suspect some premade 'blocks' of say 6" or 8" lengths that click together would be ideal, like what Psylant said. Click 'up' for a bigger tank, click 'down' for something smaller.

Best with the fixture

Edited March 17, 2016 by Iceturf