Aquarium Lights

Thyra

Superstar Fish
Jun 2, 2010
1,891
0
0
Yelm, WA
#1
Okay, I will admit - I don't understand lighting at all, although I read every post and I really do get into DIY things. I wouldn't know where to begin with LEDs or Halogen lights. But here is my simple question. I just found a stock of fluorescent bulbs from a fixture we no longer have. They are 15 watt and have the same pin set up. They say "Natural Color for Kitchen and Bath ultra" (what ever the "ultra" means) They don't have any "T" number on them. They are still in the original box. The only difference apparent to me is they don't say "Aquarium". Is there any reason they can't be used in the tank fixtures?
 

Lotus

Ultimate Fish
Moderator
Aug 26, 2003
15,115
13
38
Southern California
home.earthlink.net
#2
Is it for a planted tank? If it's not, you can use any bulb. The fixtures need to be made for aquariums (water resistant), but the bulbs are all the same. However, you may find you don't like the color visually (it might be too yellow or too red for your taste).

If it's for a planted tank, then you may need different bulbs to give the plants a spectrum that's closer to sunlight.
 

skjl47

Large Fish
Nov 13, 2010
712
0
0
Northeastern Tennessee.
#4
Hello; The "natural' label may indicate a color close to daylight. If so they may have a pleasing color. I have grown plants under daylight bulbs not intended for aquariums. I do not like the cool white bulbs.
The bulbs and fixtures need to be protected from moisture. I have used shop light fixtures in the past by putting a sheet or two of glass between the light and the tank.
 

lauraf

Superstar Fish
Jan 1, 2010
2,181
0
0
Vancouver, British Columbia
#6
I'm with Thyra - I don't really understand aquarium lighting. I still have the old wpg thing in my head but I know that's not the whole story. Can someone give me a Lighting for Dummies outline of what w versus K means for plants?
 

skjl47

Large Fish
Nov 13, 2010
712
0
0
Northeastern Tennessee.
#7
Hello: Plants have at least two variations of chlorophyll. If I recall correctly, each will operate to capture light and change it into chemical energy (sugars) that the plant uses for life processes. Sunlight has a full spectrum of light, only some of which the plants can actually use. The light colors across the spectrum are measured by us in wavelengths that we call frequency. The longer wavelengths (lower frequencies) are at the red end of the spectrum and visible light increases in frequency (wavelengths becoming shorter) across the spectrum to the blue end of the visible spectrum. We only can see a small segment of the total light spectrum.
Plants use light frequencies best in a couple of bands of the light spectrum. The rest of visible light is of no value to them. The colors that plants do not use are the colors that plants leaves appear to us. Mainly in the greens. Plants absorb the colors they can use and reflect the ones they do not use. We see what they do not use.
Daylight, natural, brite white and broad spectrum bulbs tend to have a lot of spectrum to sort of mimic sunlight. I like brite white or daylight bulbs at a frequency up to 6500k (K is the numerical symbol for frequency) I think this means that there are a lot frequencies included, from reds at the short end of the visible spectrum thru toward the more blue frequencies. Some bulbs can have frequencies higher into the blue range up around 10,000 k or so.
If you used bulbs that only put out green light frequencies the plants would be affected the same as being in the dark and could not live.
You could use plants spectrum bulbs that would grow healthy plants but the tank would appear dark as the plants will be absorbing much of the light and reflecting little.
I like to use a natural or brite white bulb that has frequencies the plants can use as well as plenty of other frequencies to be reflected to my eyes and make the tank look good.
I hope that I got this mostly right from memory. I did not put in the frequencies and temperature ranges the the chlorophylls work at because i am not sure what they are from memory. I think some of them are in the reds.