I have not changed my actinic t5 bulbs in about 2 years and in the last several months, the corals, although doing well have not been opening up to their full capacity. water parameters are all fine. could it be the bulbs? How important is actinic lighting?
How important are Actinic lights??
- Thread starter firenze00
- Start date
- Location
- Wheatley Heights, NY (long island)
Actually the actinic bulb is very important for photosynthetic efficiency. The blue bulb produces the energy in the lower wavelength which is about 430 nm. It is just as important as the daylight bulb.
This is true for deep water species because the blue wavelength is the last to dissipate. It penitrate further of all the colors before black.That's why it's suggested to ask where and how deep corals are collected before placing them under strong lighting or up top or bottom.Shallow water species on the other hand, don't need addictional actinic to thrive because they use more of the red ,yellow and green wavelength to name a few.That's why it's suggested to use full specturm bulbs meaning they have all the necessary wavelengths that closely mimic the color of the sun at 5,500 degrees K which appears IMO yellowish white light.With that said some corals are capable of adjusting to light and after 2 years they are more than adjusted to the lighting.Now if you buy new bulbs you can shock them so take caution.MO means very little so please do more research on the subject.
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- Location
- Staten Island
How important is actinic lighting???
Only as important as you seeing it.. Also sounds like a phosphate issue..
Only as important as you seeing it.. Also sounds like a phosphate issue..
I am not sure how important it is. But flourecent bulbs do degrade over time and at some point do not produce enough usable light for the corals. PC bulbs last about a year unless they are from China and then you can expect 6-7 months. T5's are supposed to last 2 years. So it may be time to change. When you do change you do need to acclimate your corals to the new light. There should be some info about that here. If not try wetwebmedia.com.
- Location
- Brooklyn, NY
- Location
- NY
+1
Actinic bulbs will 'pull' various colors from coral that we use for aesthetics.
The life of T5 bulbs vary depending upon the kelvin rating. Daylight T5's will normally last between 10-14 months. Actinic T5's can last as long as 12-16 months. There is a range given because the amount of hours people run their lights determines the overall life of the bulb. Keep in mind, fluorescent bulbs will burn MUCH longer than the stated number of months, however, the spectrum shifts so much on the bulbs that they become less effective (approaching useless) the longer they burn.
Russ
Chris Jury
Experienced Reefer
- Location
- Kaneohe, HI
The importance or lack there-of of actinics to the corals and other photosynthetic critters depends strongly on what the other light source is. Blue (and to a lesser extent violet) light are absorbed by photosynthetic critters, including the zooxanthellae in corals, with very high efficiency compared to other wavelengths. In other words, blue light of a given intensity is "better" at stimulating photosynthesis than most other wavelengths at the same intensity. Of course, that only matters if the light intensity is lower than required to saturate the rate of photosynthesis. Then it doesn't matter how efficient or inefficient light absorption is.
A pair of examples to illustrate what I mean: Say you're running two white fluorescents and two actinics and, for the sake of argument, we'll say that each bulb is equal in brightness. If you drop the actinics totally you'll cut the amount of light the corals are getting in half. For low-light corals that might not matter, but most corals would have reduced rates of photosynthesis, reduced growth, etc. Old bulbs might give 1/2 their original output. Hence, you'd be at 75% of the original light output, and probably limiting coral growth, health, etc.
Scenario two: you've got a couple of actinic bulbs, along with some strong metal halides. The halides put out 5x as much light as the actinics combined, and you've got enough light to saturate the rate of photosynthesis in many corals. Drop the actinics completely and you've still got 5/6 of the original amount of light. You may still be saturating photosynthesis in a lot of corals and, therefore, not see much change if any.
The importance of actinics depends on what they are combined with. If they are providing a significant amount of the light intensity incident on the corals (in your case, it sounds like they probably are) then they are a very important to coral growth, health, etc. If they are only contribute a small amount to the light incident on the corals, then they probably aren't very important for coral growth, health, etc. Make no mistake though, the light that actinics puts out is very good quality light for corals. The question is really just what proportion of the total light hitting the corals is coming from the actinics. If it's a big portion, they're important. If it's a tiny portion, they're not, and are probably more for aesthetics.
Regardless, I agree with the above, light quality/intensity probably doesn't have anything to do with the coral issues you're seeing. What are the results of your water tests?
Hope that helps,
Chris
A pair of examples to illustrate what I mean: Say you're running two white fluorescents and two actinics and, for the sake of argument, we'll say that each bulb is equal in brightness. If you drop the actinics totally you'll cut the amount of light the corals are getting in half. For low-light corals that might not matter, but most corals would have reduced rates of photosynthesis, reduced growth, etc. Old bulbs might give 1/2 their original output. Hence, you'd be at 75% of the original light output, and probably limiting coral growth, health, etc.
Scenario two: you've got a couple of actinic bulbs, along with some strong metal halides. The halides put out 5x as much light as the actinics combined, and you've got enough light to saturate the rate of photosynthesis in many corals. Drop the actinics completely and you've still got 5/6 of the original amount of light. You may still be saturating photosynthesis in a lot of corals and, therefore, not see much change if any.
The importance of actinics depends on what they are combined with. If they are providing a significant amount of the light intensity incident on the corals (in your case, it sounds like they probably are) then they are a very important to coral growth, health, etc. If they are only contribute a small amount to the light incident on the corals, then they probably aren't very important for coral growth, health, etc. Make no mistake though, the light that actinics puts out is very good quality light for corals. The question is really just what proportion of the total light hitting the corals is coming from the actinics. If it's a big portion, they're important. If it's a tiny portion, they're not, and are probably more for aesthetics.
Regardless, I agree with the above, light quality/intensity probably doesn't have anything to do with the coral issues you're seeing. What are the results of your water tests?
Hope that helps,
Chris
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Actinics do little to nothing for corals.
It's purely visual for us. corals don't use the lighting in that spectrum n even with deep water coral, it doesn't really matter since most home tanks are under 3 feet deep. there r plenty of reefs running with no actinics. however most will choose a higher k bulb(above 10,000k) just to make the tank look better.
It's purely visual for us. corals don't use the lighting in that spectrum n even with deep water coral, it doesn't really matter since most home tanks are under 3 feet deep. there r plenty of reefs running with no actinics. however most will choose a higher k bulb(above 10,000k) just to make the tank look better.
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Chris Jury
Experienced Reefer
- Location
- Kaneohe, HI
See my post above--sure they do
Google "zooxanthellae action spectrum" or something to that effect, you should see some hits.Chris
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