How important are actinics?

[Jiggz]

in a month or two i need to repalce my pc bulbs and i was thinking of just getting 6,700k bulbs (x4) with out actinics. are actinic bulbs as important as daylight bulbs or can i get by without the actinics? i have a 50gallon lps tank and the dimensions are 36"Lx18"Hx15"W. thanks

[Zoalander]

6700 K bulbs will make your tank look very yellow with out actinics.

[smleee]

No, actinic is not near as important as daylight. What is your current bulb setup now? I would use 10,000k and tend to not go more than a 1:1 ratio of daylight to actinic, it just gets horrendous to look at.

eee

[Jiggz]

i have 4pc bulbs running. two daylight 10,000k and two actinic. is actinic just for looks or does it serve purpose.

[gsxrguru2]

I'm pretty sure the actinics are for looks. I've heard a few say that it gives the corals a spectrum of light that they need, but I've read a lot more saying they serve only asthetic purposes.

[smleee]

They do provide "some" benefit, but not much. It is mostly for looks. I'd stay with your current setup of 10k and actinic.

eee

[Horace]

Sorry guys, but actinics DO have a purpose. You can even grow corals under pure actinic if you want. You have to remember that most corals are found deep enough where the majority of thier light is actinic in spectrum. Very few corals get blasted with 10k light all day and thats it. In fact some of the best colored tanks are those that have low PAR and high amounts of blue spectrum light. PAR is not everything by any means. Spectrum plays a very big role.

I used to think the same thing as those above...after examining several high end tanks and talking to those people, my opinion has changed.

[LowKey]

Actinics will provide photo spikes that daylight cant. Actinics represent dusk and dawn.

Are the essential? I would say yes, as you want to imitate the natural lighting conditions one encounters on a reef.

A optimum photo period
Actinics on one hour before and off one hour after yourdaylights go off

Go with a 10K or 12K daylight to complement your (Royal blue)actinics. 6700K is very yellow and you will lose some of the colouring in your fish and corals.

[smleee]

Yes, the spectrum is very important for corals, as is PAR, but when talking about "actinic" vs. "daylight" bulbs, the daylight bulbs provide a large amount of light in the 450nm range, they even have a large peak in that area, which is why it is still ok to use all daylight if you wish and also why "actinics" aren't as important as for coral growth when you have daylight bulbs; though we both agree that you do need the "actinic" (420-450nm) spectrum. Here's a graph of intensity of a 6,000k daylight T5 bulb (I couldn't find one for PC's in 10,000k or 6,000k).

http://reefcentral.com/gallery/data/500/59542sun_b.jpg

eee

[Jiggz]

aight thanks for all the responses i guess ill stay with the setup i have. thanks again for all the help.

[smleee]

Sure. :) My advice would be to go ahead and get the 2 - 10k's and 2 - actinics. Then try putting in your old 10k's along with the new 10k's (with no actinic) and see if you like it (though I doubt you will). I would also like to suggest the Current brand of bulbs as they have a proven track record and are a quality product. On another note, the "dual" actinic bulbs they make (which is a bulb that is half 420nm actinic and half 460nm actinic) are great because they will provide you with spectrum peaks in both 420 and 460 nm ranges and you will get more fluoresence from them than an actinic bulb with just 420nm or 460nm alone.

eee

[besl]

smleee - I have the Current Outer Orbit which includes actinic 420/460 nm pc bulbs along with the 10K MH. Can you explain further what value the 420/460 has over just a 420 or a 460 alone. I love the Current fixture, but was thinking I would like a more blue hue to it when I replace the bulbs.

[RichConley]

<a href=showthread.php?s=&postid=6967934#post6967934 target=_blank>Originally posted</a> by Horace
Sorry guys, but actinics DO have a purpose. You can even grow corals under pure actinic if you want. You have to remember that most corals are found deep enough where the majority of thier light is actinic in spectrum. Very few corals get blasted with 10k light all day and thats it. In fact some of the best colored tanks are those that have low PAR and high amounts of blue spectrum light. PAR is not everything by any means. Spectrum plays a very big role.

I used to think the same thing as those above...after examining several high end tanks and talking to those people, my opinion has changed.

Horace, your average 10K 250 halide puts out more blue light than VHO actinics. Actinics are for looks


The thing is, a lot of corals DO look better under actinic. The color hasnt changed, its just being accented.

[smleee]

besl:

IME and others too, using just a 420nm or 460nm alone will get you good fluoresence and provide for the proper spectrum that corals need but it is limited in what colors it will "bring out" of corals. Using a "dual" approach, you get peaks in spectrum at both 420nm and 460nm which will provide fluoresence in different corals and different colors. IMO growth wise and coral requirement wise, 420 or 460 alone is just fine; but to get the most colors out, go with the dual bulb. HTH.

Oh, the 420 is more purple and the 460 is more blue. But IMO (not tested with equipment, just my eyes), the purple has about 1/2 the brightness of the blue. I have switched between a full 420 bulb and a full 460 bulb and noticed this in dawn/dusk periods.

eee

[besl]

smleee - excellent response... I now understand the purpose of the dual wavelength 420/460 nm and will stick with them. If I still want a slightly bluer hue to the water, should I change my 10K (150W) MH to 14K (150W) MH? I I mentioned earlier this is in a Current Outer Orbit, and their 150W MH choices are either 10K, 14K and 20K.

[smleee]

<a href=showthread.php?s=&postid=6997132#post6997132 target=_blank>Originally posted</a> by besl
smleee - excellent response... I now understand the purpose of the dual wavelength 420/460 nm and will stick with them. If I still want a slightly bluer hue to the water, should I change my 10K (150W) MH to 14K (150W) MH? I I mentioned earlier this is in a Current Outer Orbit, and their 150W MH choices are either 10K, 14K and 20K.

While I have no hands on experience with MH, I do know that for a given brand of bulb going from a 10k to a 14k will make it more blue, but at the expense of output (PAR). So in a sense you will be giving your corals less usable light to grow. I believe one of the higher PAR rating 14k bulbs out there is a Phoenix bulb, but I'm not sure if that's SE or DE (I think your Orbit uses DE right?) I think you will have to research a little on PAR outputs on your MH bulbs and others, and make a decision from there.

eee

[besl]

Yes the Current MH are DE. Does anyone have any generic input on 10K MH over 14K as to appearance versus what they offer (or don't) to the corals - particularly for Current brand MH?

[Horace]

<a href=showthread.php?s=&postid=6997016#post6997016 target=_blank>Originally posted</a> by RichConley
Horace, your average 10K 250 halide puts out more blue light than VHO actinics. Actinics are for looks


The thing is, a lot of corals DO look better under actinic. The color hasnt changed, its just being accented.

While you may be right, a daylight bulb does put out a good spike in the blue spectrum as well....the point is that actinics do more than just make your corals look good. They actually do add to the very useful blue spectrum which DOES make the corals grow. The point I was making is that actinics are not worthless and do provide more than just simple flourescence. Would I want to grow my corals on actinic alone??? Definatly not, but they do add to your daylights in more ways that one. I think we all agree, that corals just simply look like arse if you dont have some strong blue spectrum in there, be it by having high kelvin bulbs or supplemental actinics.

[DesertBandits]

How do people grow the most light needy corals? Iwasaki 6500k and XM10K. Blue bulbs just look good, they don't help with growth in anyway comparable to a balanced spectrum bulb, end of story. Jiggz if you wanted more light output for extra growth, get all 10k daylights. PC 6500K only has one extra spike in red which will only help you grow more algae, for PCs 10k is what you would want. The only reason to include actinics is for a deeperwater appearance and fluorescence in certain colors. If you want to check my info just go to the store and grab some coralife PC bulbs. On the back of the box it has the spectrum charts for each bulb. The blue bulbs have only have blue but are missing all the other colors, while the daylight bulbs include the blue phosphors plus all the other colors .

[RichConley]

<a href=showthread.php?s=&postid=6997132#post6997132 target=_blank>Originally posted</a> by besl
smleee - excellent response... I now understand the purpose of the dual wavelength 420/460 nm and will stick with them. If I still want a slightly bluer hue to the water, should I change my 10K (150W) MH to 14K (150W) MH? I I mentioned earlier this is in a Current Outer Orbit, and their 150W MH choices are either 10K, 14K and 20K.

Besl, make sure you look at the charts of wavelengths. If I remember correctly, 10K and 20K actually have large violet spikes, and 12-15K bulbs have blue spikes. Look at the bulbs though.

[RichConley]

<a href=showthread.php?s=&postid=6997432#post6997432 target=_blank>Originally posted</a> by Horace They actually do add to the very useful blue spectrum which DOES make the corals grow. The point I was making is that actinics are not worthless and do provide more than just simple flourescence. [/B]
Horace, actinics do help, and 10K w actinic is better than 10k, the thing is, 2x10K is better than 10K w actinic.

Take a 10K, chop out the non blue spikes, and you have an actinic bulb. The only advantage over a 10K, is the look that some people like.


I run all 10K, and like the crisp white look, I hate the blue-wash look.

[Horace]

<a href=showthread.php?s=&postid=6997565#post6997565 target=_blank>Originally posted</a> by DesertBandits
How do people grow the most light needy corals? Iwasaki 6500k and XM10K. Blue bulbs just look good, they don't help with growth in anyway comparable to a balanced spectrum bulb, end of story. Jiggz if you wanted more light output for extra growth, get all 10k daylights. PC 6500K only has one extra spike in red which will only help you grow more algae, for PCs 10k is what you would want. The only reason to include actinics is for a deeperwater appearance and fluorescence in certain colors. If you want to check my info just go to the store and grab some coralife PC bulbs. On the back of the box it has the spectrum charts for each bulb. The blue bulbs have only have blue but are missing all the other colors, while the daylight bulbs include the blue phosphors plus all the other colors .

BTW, who is growing SPS under PC??? Not many that I know of so lets just drop the whole PC/SPS discussion right now.


I would also wager to say that a T5 tank that has pure Blue+ lighting, especially overdriven blue+ would not lag too far behind one that is nothing but 6500k bulbs.

You really must be an expert on halide lighting eh? Im sure you know exactly what all the great SPS tanks run for lighting dont you? Well I am here to tell you my buddy (GQJeff) has one of the finest SPS tanks in the coutnry. He runs nothing but XM 20k halides (one of the lowest PAR bulbs out there) as well as T5 2 Blue+ and 2 VHO Super actinic and his tank has as good or better colors and growth than any 10k halide setup out there. Pretty much all the big names in SPS know of his tank so feel free to ask around. Its not all about super high PAR numbers. Im not going to waste my time trying to change your mind because its obvious your massive experience with growing SPS is far greater than mine....RIGHT!

Like I pointed out before, once you get below about 30ft deep (where the majority of corals come from), the light is filtered down to almost exclusivly blue spectrum anyway. So once again, actinics are far from worthless.

I will also state that most of you people out there have the false impression that Lighting is the most important thing to SPS growth/color. Infact the most important thing by far is water quality and low nutrients, proper feeding of your corals. Second is flow and third is lighting. So argue with me all you like, but simply strapping 10k halides on your SPS isnt going to cause your stuff to grow any better than somone who has the other things accounted for and have sufficient PAR output (XM 10k type PAR levels are far from a required level)

[Horace]

<a href=showthread.php?s=&postid=6997734#post6997734 target=_blank>Originally posted</a> by RichConley
Horace, actinics do help, and 10K w actinic is better than 10k, the thing is, 2x10K is better than 10K w actinic.

This is kind of a rediculous statement because no one coral gets much of both halides output because you cant fit 2 over top of one coral. Think of it this way if you put one 10k in the center of the tank, the coverage would be so horrible that it wouldnt be very good anywhere accept right under that halide. With 2 halides, of course its going to be better because the PAR will more stable throughout the tank (given its 4' tank). Also it depends on what type of actinic your using. If your using PC actinic, of course your not going to get jack for growth out of them. But if you decide to use overdriven T5 Blue+ then your talking about a whole different ball game my friend. The T5 blue+ puts out only slightly less par than even the daylight bulbs. So before you can say that actinics dont do jack, you have to be talking about a specific setup. In the case of a 10k XM bulb on magentic ballasts, with PC supplemental actinic, I would have to totally agree with you. However if you had the T5s instead, that becomes much less true, espeically if you have a higher kelvin halide.

[spoon25]

hey i am growing lots of sps under pc's....lol....lets see i have all actinics and my setup is blasting with color ang growth, now i am using 250 15k bulbs and also using 96 watt actinic pc's and 110w vho super actinics and my tank looks real nice when the halides come one...they have a nice hint of blue to them, but just enough white to make colors come right out, except for certain sps that i have moounted high up mor towards the vho's... anybody need some brand new pc bulbs and brand new electronicc ballast PM me plz.....but anyhows i am running all actinics and my tank seems to be doing fine...thanks

[ZoeReef]

Here's one of the most stunning tanks you will ever see, Only lighting is pure T5.

http://reefcentral.com/forums/showthread.php?s=&threadid=700454&perpage=25&pagenumber=1

[RichConley]

<a href=showthread.php?s=&postid=7003270#post7003270 target=_blank>Originally posted</a> by Horace
This is kind of a rediculous statement because no one coral gets much of both halides output because you cant fit 2 over top of one coral. Think of it this way if you put one 10k in the center of the tank, the coverage would be so horrible that it wouldnt be very good anywhere accept right under that halide. With 2 halides, of course its going to be better because the PAR will more stable throughout the tank (given its 4' tank). Also it depends on what type of actinic your using. If your using PC actinic, of course your not going to get jack for growth out of them. But if you decide to use overdriven T5 Blue+ then your talking about a whole different ball game my friend. The T5 blue+ puts out only slightly less par than even the daylight bulbs. So before you can say that actinics dont do jack, you have to be talking about a specific setup. In the case of a 10k XM bulb on magentic ballasts, with PC supplemental actinic, I would have to totally agree with you. However if you had the T5s instead, that becomes much less true, espeically if you have a higher kelvin halide.
(in responce to your hypothetical situation, the Blue+ are like 12K bulbs, not actinics, and you'd still get better growth from changing them to 10Ks)

You totally missed my point.


A 10K bulb puts out almost exactly the same amount of blue light as a 14K bulb. It just also puts out more yellow and green and red light.

SO, yes, you can grow corals with actinics, but, they will always grow better under 10Ks. By using an actinic bulb as opposed to a 10K, you are chosing on aesthetics alone, and not coral growth. So yes, Actinics are useful, but not at the expense of a 10K bulb.


When you replace a 10K with an actinic bulb, you lose red and yellow light. You dont gain any appreciable amount of blue light.

Think of it this way:

Running a 10K bulb is like using a red LED, a yellow LED, and a blue LED. Running an actinic 03 bulb is like just running the blue LED.

It looks bluer becaues the other colors are gone. Less useable light, bluer visible color.

[Mike.B]

I cant see a regular 10k bulb having as much blue as actinic bulb, the actinic has to have more blue light, I would say the the 10k bulb is like a yellow LED a red LED and a blue LED, but the actinic 03 would be like having 3 blue LED's.

Another thing, wouldn't the other light colors in the bulb(10k) more or less cancel out the blue light because of the other colors?

[NCreefwannabe]

so how about running 12k with actinics? Would that be better than running them with a 10k?

[rickh]

I switched from running 1:1 daylight/ blue to 1:2 daylight/blue. It's only been a few months, but the coral appear to be doing fine. I like the coral to "glow". R