Discussions on lighting SPS tanks

[gjuarez]

Lets discuss about lighting an sps tank. Lets talk about growth, color, PAR, photoperiod, wattage, kelvin, and all else that applies. I know that water quality plays a huge role on these factors, but for this thread lets assume that water quality is optimal.

Does spectrum really play a role on growth? Could it be that higher kelvin bulbs have less par? If so, could a 400w 20k bulb compare to a 175w 10k bulb in growth results?

Does anyone have a combination of 6.5k - 10k - 20k bulbs or others? I have read that combinations betweeb kelvin ratings help in hitting all three types of zooxanthellae but it was very brief. Could someone expand a little further on this subject?

Talk about anything you want, as long as it relates to the thread please. Remember that there is other factors that contribute to growth and coloration, so for this thread we are keeping in mind that all other conditions are met. VHO only and T5 only users for sps are encouraged to give input. Lets make it interesting.

Jerry

[hobogato]

well, as far as my lighting goes -

3 @ 250 watt 14k coralvue, 325 watts of PC true actinic, 195 watts of PC 50/50 and lots of blue LED moonlights

- i am seeing about 1/4" growth a month on average, with some a little faster and some much slower. many of my sps browned out as soon as i added them, but are now starting to really color up. they seem darker than original color, with more green highlights. one frag i got from sean was pink/purple when i got it, and now - 6 wks later - is emerald green with burgandy polyps.

[gjuarez]

Have you always had 14k? Did you at one point have 10k? If so, what do you think it has done to your growt and color?

[hobogato]

first MH i had was a coralvue 10k on my 125gal. i did not like the look of it, and i bleached some sps by moving them up too fast. switched to XM 15k, and liked them much better. i just switched to the coralvue 14k about 2 weeks ago bc two of the XM's quit working in the 4-6 months since i bought em and that will just get way too expensive. i went with the coralvue 14k because they are similar in appearance to the XM 15k, just a tiny bit more white, but noticably brighter. since i switched to the 14k, the tips on a few of my acros that were turquoise have started to turn a more royal blue color :skeezy so hopefully that will be a trend.

not the best pic, but if you look closely, you can see some of the tips getting a much darker blue.

http://i30.photobucket.com/albums/c329/hobogato/bluetip.jpg

[hobogato]

sorry for the double post

[gjuarez]

Brian, i do understand that flow is a big factor as far as growth and coloration. I guess I forgot to mention that. I only mentioned water quality. For future reference, let say that all other factors excluding lighting are optimal.

Brian, do you think its the higher spectrum that causes growth to slow down? Like mentioned earlier, do you think it could be that higher kelvins have less PAR values?

[Jenn]

Are there any reasons not to use a 400w XM 20k? That is what I have right now (for 2 weeks) and everything seems to like it. I just see most of you seem to prefer the 10k w/ actinic supplement.

[carlinsa]

i have a 125 with 2-250watt mh 10k xm bulbs and 4-140watt VHO actinics. 1060 watts total.

havent had it set up very long so i cant tell you about the growth like other probably can. i am thinking about adding one more 250 to the center with a 10k xm bulb just for a little more light. but right now it is just a thought cause everything is doing great and NOT DIEING. i had a coral kind of brown on the tip but in the past 2 weeks it has gotten its color back nicely.

as fpr flow i have a mag 18 for a return and a OM hooked to a DART. not near as much flow as brian but pretty good amount.

[carlinsa]

Are there any reasons not to use a 400w XM 20k? That is what I have right now (for 2 weeks) and everything seems to like it. I just see most of you seem to prefer the 10k w/ actinic supplement.


the only reason is i have been told there is better growth with a 10k. a 20k bulb has a slow growth rate. someone with more experience will be able to tell you more in depth

[akm]

Higher kelvins definitely have a lower par the lower kelvins. 6500K bulbs have alot of par meaning that there is more light available that the corals can use causing them to be able to grow faster.

[JimD]

Jenn, Ive used the 400w 20k xm's before in the past, in my opinion, they do a pretty good job on just about everything including some acros. The growth wont be as noticable as a 10k, but ok none the less. The main problem I had with the 20k's is that the usable output and color stability usualy went out the window at about six to eight months causing a washed out appearence and less color distinction. The reason for 10k's and actnics is for acro growth, 10k's are much brihgter and do a better job with photosynthesis. The actinics help bring out the colors for the most part. Its all a matter of preferance.

[Jenn]

Makes complete sense - thanks guys. This bulb is approx. 6 months old, so I will switch to a 10k soon and see how that works.

[gjuarez]

Does anybody know where I can information regarding kelvin and growth. Gary once mentioned that he could grow acros with any light, as long as there was enough intensity in PAR value. This leads me to believe that its not the spectrum that really has an impact on growth, but the PAR value. I have no scientific research, but let me provoke your minds. For example, lets compare a 175w 10k bulb versus a 400w 20k bulb. The difference in wattage makes up for the decreased par in the 20k bulb. Lets assume that they both give us a par value of 300. Do you guys still think that the spectrum will play a role?

[Richard]

http://www.reefs.org/library/aquarium_net/1298/1298_2.html

[gjuarez]

Thanks Richard, that was a great article. I thought it was a very interesting read. Here is the conclusion of the study:

"Our short study suggests that light is the most important factor for the promotion of coloration in this Acropora species. Our observations also suggest that pigments may not become apparent for 30 days or so after light levels are increased. This may take slightly longer if fragments or cuttings are taken from a parent colony, as they seem to first direct their energies to recovery.

Does lamp spectra influence coral coloration? We tend to think not (although caveats do apply). Our contentions are these: Zooxanthellae play an important part in coral growth and, hence, pigmentation. Zooxanthellae require only a certain amount of light for the process of photosynthesis. Further, zooxanthellae require light in the blue and red portions of the spectrum (and other portions if accessory pigments are present). When light levels no longer increase the rate of photosynthesis, the process is "saturated". We believe that light saturation can occur in particular portions of the spectrum (that is, blue or red or green) with most lamps. Lamp Kelvin temperature does not matter if sufficient amounts of certain portions of the spectrum are produced. However, aesthetics play an important part in display aquaria and lamp Kelvin temperature is likely a prime consideration."



It mentions about coloration of sps but didnt mention anything about growth. I will keep researching reefs.org for more info on this.

[gjuarez]

BTW, is anyone playing with different photoperiods?

[GaryP]

Does spectrum really play a role on growth? Could it be that higher kelvin bulbs have less par? If so, could a 400w 20k bulb compare to a 175w 10k bulb in growth results?

Does anyone have a combination of 6.5k - 10k - 20k bulbs or others? I have read that combinations betweeb kelvin ratings help in hitting all three types of zooxanthellae but it was very brief. Could someone expand a little further on this subject?

The lower the K value, the higher the PAR (photosynthetically available radiation) value. A 20K bulb has almost half that of a 10K, etc. As for 3 types of zooanthellae, you got me there. What I have read is that corals could care less as far as wavelenght, light is light. Where it does make a difference is on coral color pigmentation.

The lower wavelenghts, and especially 420 nm, are what cause many pigments to be produced. Those pigments are similar to us getting a sun tan. Its how they protect themselves from UV radiation in shallow water. 420 nm is the spectrum closest to UV in the visible spectrum. UV-A is between 320-400 nm. So, in a way, its like we are putting corals on the equivalent of a tanning bed. The blue and purple pigments are most commonly produced by this spectrum.

420 nm is what you get from true actinic bulbs like the VHO bulbs. Some of the MH, PC, and T-5 bulbs also produce 420 nm. However, don't think that every blue bulb is actinic. Many of the "blue" bulbs are actually 460 nm. 460 nm doesn't have the same impact on pigment production that 420 nm does.

In many cases, a 10K bulb may actually produce more 420 nm color then a 20K does, even though it may look "bluer."

Take a look at the three spectrum charts for Ushio bulbs in the link below to see what I mean. Not only does a 10K have a higher PAR, it also produces more 420 nm. The 20K has a very small 420 nm peak compared to the 10K and 14K bulbs.

http://www.ushio.com/Files/Aqualite.pdf#search='Ushio%20spectrum'

[GaryP]

Again, on the topic of PAR vs. K value. Here is some more data from Ushio. I'm not particularly going to Ushio for any particular reason other then their site has good information.

These values are PAR/watt for various double ended Ushio double ended 175 watt bulbs. These data are just intended to give you some basis of comparison and to illustrate my statements in the previous post. These data may not be typical of other brands of bulbs.

6.5K - 52
10K - 47
14K - 47
20K - 22

I know many of you prefer 20K bulbs because they are "pretty." However, from this you can see that you will require twice as many bulbs to get the same level of PAR. The other problem is that you might get nice blue and purple, but your pretty pink, red, and yellow corals may not look as nice with a 20K. I personally think of a 20K as a supplement bulb, not a primary one, and not necessarily a good one because you aren't going to get much 420 nm from it.

In my systems, I use actinic fluorescents for that supplementation.

[gjuarez]

Gary, thanks a lot. I had been waiting for your input. So what do you think about spectrum and PAR in terms of growth. If you have 300 Par value of 10k and 300 par value in 20k, (taking into consideration that the 20k will be higher wattage to produce 300 par value) which one will have the best growth results? In this case both of the bulbs have the same intensity (300 par value) but different spectrums. People say that lower kelvin bulbs allow for faster growth. Could it be because they have almost double in PAR value? Could it be possible that people have ignored that factor? I can see where pound per pound (250w vs 250w), a lower spectrum bulb will have better results in growth because of the intensity, but what about a fight where a higher kelvin bulb cheats (175w 10k vs. 400w 20k) where each has a par value of 300. I am the type of person that likes to think beyond the scope of things, but to me it could make sense that a lower kelvin bulb would alter the growth of a coral because the intensity, not neccesarily the spectrum. Now I can see where spectrum plays a role in pigmentation, that was explained very nicely. I am not even sure if I make sense, just trying to think outside the box.

[GaryP]

That's what I said earlier, zooanthellae could care less on the spectrum as far as they are concerned. A photon is a photon is a photon. Its all about PAR value as far as growth is concerned.

Spectrum does make a difference for pigment production. If I was running a frag farm, I would be running 6.5K on the mother colonies for growth, then switch to a 10K with a lot of 420 nm to develop color before marketing the frags. Anyone know what the color of natural sunlight is?

5.5K.

Am I recommending you run 5.5K bulbs? Of course not. I will say that my first SPS tank had 6.5K and the corals were growing out of the tank. Was it pretty? Heck no! The "art" or reefkeeping is finding a balance between color development, growth, and appearance. 20K is pretty, but low growth. 6.5K is great growth but ugly. That's why most experienced reefers stay in the 10-14K range where there is a happy medium. In an ideal world with a large tank I would run 3-4 different bulbs so that everything will be there and you don't have to have to settle for anything but full spectrum in all ranges. My best suggestion is to study the spectrum of a bulb you are buying and make sure its giving you what you are looking for. Then you just have to hope the spectrum they provide is what you get in the bulb you buy. I just went through that with a bad XM bulb.

[gjuarez]

So far with the bulbs I have researched on I think the one that best suits my needs is the reeflux 10k. It gives good par and nice colors. Have you tried or heard about them yet?

[hobogato]

mark (theotherguy) just put reeflux 12k on his tank, you might keep track of his thread.

[GaryP]

So far with the bulbs I have researched on I think the one that best suits my needs is the reeflux 10k. It gives good par and nice colors. Have you tried or heard about them yet?
I looked into them when the recent thread came up on them. What I didn't like about them was almost no 420 nm. That may be OK in your system is you have enough true actinic supplementation.

Look here to see what I mean:

http://www.advancedaquarist.com/2005/5/aafeature_album/fig1-Coralvue400W-10K.gif/view

[GaryP]

Maybe Todd will jump in here. He is very knowledgeable about bulbs.

[gjuarez]

Yeah, I think they peak at 460nm. That is the reason I bought icecap 430 and some URI Vho actinic bulbs for my 29g. I will combine those with a 250w reeflux 10k and provide 420nm through the VHO. I think this lighting setup will work good for me.

[gjuarez]

I am bumping the thread for more discussions and as reference for a friend. Also, does anyone know what effect moonlights have on a reeftank.

[lachrimae]

Here's a related article (though a few years old):

http://www.advancedaquarist.com/2002/2/aafeature

[scuba_steveo]

I started with Hamilton 14K, tried the new Coralvue Reeflux 10K (or was it 12k Todd?) and now I am using the EVC 14k. I really liked the color of the tank under the hamilton. The reeflux was too wite for me. I only have 2 VHOs for actinic supplement. The coral color under the EVC 14k is awesome but the tank is a little too blue. I might go back to Hamilton, but for now I am staying with the EVC.

[gjuarez]

I really liked this thread, so I am bumping it.. Great conversations and good topic. I think some people could benefit out of this. I am toying with the idea of using t5 on my 30g long for a mainly sps tank. t5 experts, chime in

[Mr Cob]

Man dude...these are like three year old threads you are bumpin...kind of interesting to read through them to see how much some of the reefers have progressed...kind of wierd to hear Ace talking about MH on a 125 gallon! LOL...him and Mike are known for the sun tubes these days.

[gjuarez]

jaja. I know.. These were the good old days.. There is plenty of threads that I can bump but i wont, only the interesting ones. These threads are very informative so it doesnt hurt.

[Mr Cob]

true that.

I personally like 14k MH bulbs the best. XM. I don't even need actinic lighting with them...in fact when I turn the actinic lights off you can barely tell a difference. I use my actinic lighting to increase my viewing time of the tank 2 hours pre and post MH. I run the MH for 6 hours a day and a total of 10hours on the actinics.

[gjuarez]

I really like my tanks to have some sort of actinic supplimentation. Alot of mh bulbs put out the blue light, which is more in the 460nm range. True actinics are 420nm. Until today, I have never had anything come close to VHO actinic. Is there any t5 bulbs out there that can close or perhaps even better than VHO.

[LoneStar]

URI now makes true actinic bulbs for T5 fixtures now.

[brewercm]

My T5 setup is using two true actinics from URI and three actinic whites which are rated about 12k I believe.

[JimD]

Im not a fan of 14k bulbs at all, too monochromatic. Theres nothing like a good 10K with true actinic supplimentation. I have yet to see a single bulb look anywhere close to the 10k/vho combination.. Oh yeah.... IMO.