A better lighting effect with the addition of one blue bulb

[qihst1]

Hi,

I posted a message a couple of months ago regarding a better lighting effect with a combination of different light bulbs. I found out that a combination of different bulbs (with different "color temperatures")
were used for a 135 g discus show tank in a local Wetpets Store.

Somebody tried it immediately and had a better light effect, while a few other folks believed in regular bulbs and thought that the intensity is the key rather than the spectrum of light.

I tried it myself today. I bought a Coral life 20,000 K bulb (I bought it with $30 and, I guess, we can get it for $17 at Dr. Foster & Smith) and mixed with two regular bulbs. My wife immediately noticed the effect and she liked it a lot. :D It achieved a well balanced color in combination with other full-specrum bulbs, and yet, not as expensive as with all salter water bulbs. ;D It made water more crystal clear and enhanced the colors of my fish. It gives out a lot of blue light, it would be good for plants as well. I will be able to see that in a few weeks.

Paul ;)

[ChloroPhil]

Paul,

Changing the color spectrum of your lighting, or mixing different spectra actually has minimal actual effect on a freshwater aquarium. Increasing the spectrum output on your bulbs really only enhances the corresponding colors in your fish. The additional blue light doesn't make your water clearer by any means, although it may decrease the visibility of some particles. What has likely happened is that by adding more light to your tank you're able to see into it better, giving the impression of clearer water.

Also, by adding another bulb rather than replacing an exisiting one you're increasing the intensity of the light that reaches your plants. That increase in amount is what will benefit your plants, not the addition of light in different color temperatures. If you want to get true results you'll need to buy two or three different sets of bulbs for your fixtures and use sets of different bulbs over a given period and record the differences in growth.

Lighting, Spectra, and their effect on plants is pretty interesting stuff. Without getting too techincal; red light encourages shorter, stockier growth and blue light encourages taller, leggier growth. It's important to remember that 99% of our aquarium plants are actually amphibious species that live in the marginal areas of bodies of water with the rest living in the shallow regions. This means that our plants receive full spectrum sunlight and need a good mixture of Red, Green/Yellow, and Blue light. The best bulbs to simulate this are those in the 5300-6700*K range.

[ronrca]

Using higher or lower Kelvin tubes in the planted tanks really only is more for appearance rather than beneficial for plants. I also mix spretrums to achieve the an appearance I like. ;)

[yellow sub]

I am not trying to make waves, but, I am not convinced that spectrum does not have anything to do with plant growth. I am not a plant expert but I have some experience...I keep floating plants in all of my tanks and when I first set up shop lights on my racks I used 4100K 83 CRI bulbs, I used these bulbs just because they were hanging around and I wanted to save a few bucks. Never had plant growth. Switched to 5000K 92 CRI bulbs and the plants are now growing and doing very well.

Stephen

[ChloroPhil]

Spectrum very much does have to do with how plants grow. It affects their shape rather than the actual rate of growth though. Light intensity has everything to do with how well and how fast your plants grow.

[aix]

Yes, spectrum has everything to do with plant growth. In the nature in the mornings end evenings the light is about 1500-2500 K, looks red. In the midday sun about 7000K. But with cloudy sky it can get higher than 10000K since red light is all sucked in to the clouds. As somebody here mentioned, plants need mostly red and blue light. Red for length and blue for thickness. Since red light is sucked very fast in the water (50%-70% within 50cm) the eye can not always detect the actual situation and plants are not growing OK since they can not get enough red. If only intensity would be limiting factor, we could use usual bulbs. Instead they tend to grow only algae, wihich does not have such needs and can basicly grow under any conditions. If somebody wants his plants to feel good, I would recommend a system with 2 different light- lower K in the morning and evening and higher in addition at daytime. With CO2 addition and such lighting (other factors in OK)your plants will grow faster than you can sell them.

[qihst1]

Yes, spectrum has everything to do with plant growth. In the nature in the mornings end evenings the light is about 1500-2500 K, looks red. In the midday sun about 7000K. But with cloudy sky it can get higher than 10000K since red light is all sucked in to the clouds. As somebody here mentioned, plants need mostly red and blue light. Red for length and blue for thickness. Since red light is sucked very fast in the water (50%-70% within 50cm) the eye can not always detect the actual situation and plants are not growing OK since they can not get enough red. If only intensity would be limiting factor, we could use usual bulbs. Instead they tend to grow only algae, wihich does not have such needs and can basicly grow under any conditions. If somebody wants his plants to feel good, I would recommend a system with 2 different light- lower K in the morning and evening and higher in addition at daytime. With CO2 addition and such lighting (other factors in OK)your plants will grow faster than you can sell them.


It sounds right to me. I had a Botany MS 15 years ago. However, I am not in that field anymore. I have to ask my classmates with a strong Plant Physiology background.

I have some Anachiris (a high light plant) and it is not doing very well with my regular fluoresence bulbs at about 2.5 w/g intensity. I will find out whether the 20,000 K light bulb can turn them around or not.

All I want to say it that, although the light intensity is the most improtant, you still need a bright blue bulb which enhances the color of you fish. Everybody agrees? 8)

Paul

[aix]

Unfortunately can not help with Anachiris, never had it.

[ronrca]

I thought this was an interesting article:
http://www.hydrofarm.com/content/articles/flour_lights.html

[qihst1]

I thought this was an interesting article:
http://www.hydrofarm.com/content/articles/flour_lights.html



It is a good article.

As it said here "Critical experiments show that maximum growth of most plants under cool white fluorescent lights will be equivalent to or better than that obtained under the blue-red phosphors. Work by V. A. Helson, Canada Department of Agriculture, Ottawa; and J. W. Bartok and R. A. Ashley, University of Connecticut, indicate that there is no advantage to the use of blue-red fluorescent tubes TEXT. Some of the names of these special tubes are Grolux, Plant-Gro, Plant Light, Vita Light and Optima. TEXT.

A right type of light does enhance the color of fish. This is what we are getting.

paul

[aix]

If interested there is some interesting stuff in www.tropica.dk