Whenever I research lighting, most units come with an atinic bulb. I always ask to switch it out for a midday or a daylight. But now I'm unsure as to whether I should be doing this
The following quote was part of a discussion on CCA:
Actinics serve no purpose for plants.
Sorry Fran but that's not true. Actinics are great for growing plants. The light output of an Actinic directly matches the wavelengths in the blue/violet range that chlorophyll a absorbs in. Chlorophyll a is the primary pigment found in all photosynthetic organisms. When matched with a lamp that has good red light emission (the other peak absorbancy found in Chlorophyll) it can grow plants very well and more efficiently than a full spectrum lamp that wastes energy in the green/yellow wavelengths that plants do not use.
The downside is that actinics are not bright to the human eye and the aquarium looks dimmer. Add in a very red lamp and you get a strange purple look to the tank.
I would suggest keeping one of your actinics and replacing the other with a red lamp like a Coralife Colormax. That way you get a lot of blue/violet, a lot of Red, and a lot of green yellow (the 6700K) to make the tank look bright.
Actinic bulbs?
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DonkeyFish
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*Some* Actinic bulbs do indeed hit the exact wavelength (one of the two) plants want.
Others miss it entirely. Actinics are not like our typical bulbs, they are geared for pretty specific wavelengths, and not all the same ones.... the above statement about them being good for plants *can* be true, but it is not *always* true.
Original quote is correct in that it needs to be matched to a bulb with intensity in the red range plants also look for to be of any real use. This is an important note!
Why is it important?
The problem with not "wasting energy" as posted above is that while you can get pure blue/red bulbs (particularly in LED array setups), they look HORRID to our eye. You don't want to do it in a display tank.
And by the time you put in enough "wasted" light to make the actinic not make everything look odd and all "neon" like - well, assuming HO or similar bulbs, you may as well not have had it, because you are gonna be in supernova light levels.
If you don't care as much about it being an eye pleasing display... by all means!
I've always replaced them, even when the spectrum was right, because they look funny - I don't want neon colors, I want "real" colors when I look in my tank. It isn't about dim, it is about my tank looking like it has a blacklight and neon colors in it. The 70's are gone.
There is a myth as well, and I do not know if it is true or not, that says too much pure actinic in freshwater is an invitation for algae. As blue (actinic) is often overpowered compared to red spectrum outputs when it is utilized... part of me wants to believe that myth, as it is indeed an imbalance.
PS - Why are bulbs made actinic for saltwater in the first place? Because the reds fade out twice as fast as the blues as light penetrates water depths. Corals are deep (relatively speaking) under the water - they adapted and evolved to use only blue light. Freshwater and tidal plants are not deep underwater.... they need a balance and plenty of the red too, as they never made that evolution.
Others miss it entirely. Actinics are not like our typical bulbs, they are geared for pretty specific wavelengths, and not all the same ones.... the above statement about them being good for plants *can* be true, but it is not *always* true.
Original quote is correct in that it needs to be matched to a bulb with intensity in the red range plants also look for to be of any real use. This is an important note!
Why is it important?
The problem with not "wasting energy" as posted above is that while you can get pure blue/red bulbs (particularly in LED array setups), they look HORRID to our eye. You don't want to do it in a display tank.
And by the time you put in enough "wasted" light to make the actinic not make everything look odd and all "neon" like - well, assuming HO or similar bulbs, you may as well not have had it, because you are gonna be in supernova light levels.
If you don't care as much about it being an eye pleasing display... by all means!I've always replaced them, even when the spectrum was right, because they look funny - I don't want neon colors, I want "real" colors when I look in my tank. It isn't about dim, it is about my tank looking like it has a blacklight and neon colors in it. The 70's are gone.
There is a myth as well, and I do not know if it is true or not, that says too much pure actinic in freshwater is an invitation for algae. As blue (actinic) is often overpowered compared to red spectrum outputs when it is utilized... part of me wants to believe that myth, as it is indeed an imbalance.
PS - Why are bulbs made actinic for saltwater in the first place? Because the reds fade out twice as fast as the blues as light penetrates water depths. Corals are deep (relatively speaking) under the water - they adapted and evolved to use only blue light. Freshwater and tidal plants are not deep underwater.... they need a balance and plenty of the red too, as they never made that evolution.
Dave
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scientist0724
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Yep, they might grow plants if you supply a red bulb too, but unless you're purely farming plants, and don't care how the tank looks, they're not much use to us. I have one of those LED bulbs, and it really makes the tank look awful -- plants grow, but I added a regular full-spectrum fixture to the tank to turn on when I want to view it.
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ddavila06
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you should post a picture of your tank with the LED light for plants, remember?? i cant make the exact look but was very strong!krisw wrote:Yep, they might grow plants if you supply a red bulb too, but unless you're purely farming plants, and don't care how the tank looks, they're not much use to us. I have one of those LED bulbs, and it really makes the tank look awful -- plants grow, but I added a regular full-spectrum fixture to the tank to turn on when I want to view it.
Damian Davila
"Fishes-up, chill, Plants too"
"so many plants, so little space!"
"Fishes-up, chill, Plants too"
"so many plants, so little space!"
I alway like to use the Kelvin scale just like I would with a camera, 3000 to 4000 sunrise or sunset on a clear day, 5000 to 6500 clear blue sky in the heat of the day, 6500 to 8000 a moderately overcast sky, 9000 to 10k shade to heavily overcast skies.
I know 10k bulb will grow plants but I'm using 5,500 bulb with less wattage than I have ever used before and getting good color out of red plants. I also use a weak fixture with 6,700 bulbs for my sunrise/set cycle, but I'm trying not to go over 8k or under 5k.
Current - USA uses a 12k bulb for their lunar lights to replicate the moon's glow, and I think this is also an overlooked aspect to the planted aquarium that helps with breeding and other cycles.
I know 10k bulb will grow plants but I'm using 5,500 bulb with less wattage than I have ever used before and getting good color out of red plants. I also use a weak fixture with 6,700 bulbs for my sunrise/set cycle, but I'm trying not to go over 8k or under 5k.
Current - USA uses a 12k bulb for their lunar lights to replicate the moon's glow, and I think this is also an overlooked aspect to the planted aquarium that helps with breeding and other cycles.
