Normal ol' light bulbs

[CodKing]

I'm interested in peoples experiences with low Kelvin bulbs regarding low light, slow growth planted tanks. My partner's father tells me he used to grow plants under 'normal ol light bulbs'. Makes me wonder what people have tried other than T type and other fluros.

[Ira]

I'm interested in peoples experiences with low Kelvin bulbs regarding low light, slow growth planted tanks. My partner's father tells me he used to grow plants under 'normal ol light bulbs'. Makes me wonder what people have tried other than T type and other fluros.

You mean like incandescent bulbs? Sure they work. If you don't mind paying 4 times as much in electricity.

[blueether]

But think of the watts per gallon :digH:

[CodKing]

Cool, I thought a low Kelvin rating would make them not so useful.

[spoon]

the old timers will tell you how well they did(sorry alan :digH: ) but i think it was more a case of balancing light with nutrients and co2

[alanmin4304]

Its all we had in the day :sage:

[livingart]

i like them new fangled eco bulb thingy's

use them to grow phyto plankton

and to light the way for my walking frame in the dark :sage:

[Ira]

Its all we had in the day :sage:

That was after you upgraded from having your slaves hold mirrors to reflect sunlight inside and holding torches above them on overcast days, right?

[Stella]

That was after you upgraded from having your slaves hold mirrors to reflect sunlight inside and holding torches above them on overcast days, right?

Ah those were the days! :cofn:

[Joe]

Kelvin rating is unimportant in aquarium bulbs, but is useful in standard industrial bulbs. It tells you the colour temperature of the light. However, this can look completely different depending on the spectral output of the bulb. For example, Arcadia Plant Pro tubes have a colour temperature of 7,5000K, which should be a cool white colour. But the actual colour is pink, because they have high peaks at the red and blue end of the spectrum. Spectral output is measured in nanometers. This is sometimes displayed on the packaging of the bulb, mainly aquarium bulbs though. You will unlikely find it on an incandescent bulb or industrial flouresent tube, because they aren't sold as aquarium bulbs and so the people who use them only care about lumens and how bright the bulb is, and they don't care about its spectrum. Sometimes though if you go on to the website of the brand you will be able to find a graph of its spectral output. Plants like blue and red light, and are most sensitive to 430nm (blue) and 650-680nm (red). The red light improves the colouration of the plants, but also the stem elongation too. Using a bulb that is high in the red end of the spectrum leads to very leggy growth. That's where the blue comes in. It promotes healthy leaf development and bushy, compact growth.

Generally, 0-5,800K is displayed in a orange-redish light, meaning that it is high in the red end of the spectrum, and 6,000K-10,000K is blueish, slowly becoming more blue the higher the colour temperature. They also tend to have a lot of green in the spectrum. A lot of aquarium bulbs have the spectral graph altered, which is why the colouration of the bulb is different to what it states the colour temperature is. This is designed to look pleasing,to grow plants, or both.

So when you get normal bulbs, a colour temperature of 6,000K - 10,000K is fine for growing plants, and generally has a good amount of blue light. You could mix a couple of bulbs that are 6,500K-10,000K with a bulb that is 3,000K-5,800K, so you have a rough idea that you are providing a good amount of blue light for the growth, and a bit of red light for colouration.

HTH

[Caryl]

Torches? What are those? We used candles

[Ira]

Torches? What are those? We used candles

They're big flaming sticks, not as fancy as candles.

[CodKing]

Spot on Joe! That's the kind of explanation I was looking for, thanks! :thup: