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johnnstacy
09/05/2006, 01:47 PM
Today I heard two things I have never heard before. Here were the two statements given by some who has been in the trade forever:

1. Light intensity has no bearing on color

2. Spectrum of bulb has everything to do with color

Here is why I was so surprised to hear that. I currently have a 250W DE setup and I'm running 10k Ushio bulbs. Today, I was getting ready to buy the Lumenarc III mini's in a 400W SE. I told him what I was planning on doing and he asked why. I told him I was looking for more color. This is when he said that it had nothing to do with whether I was using 250 DE or 400 SE or 400 DE or anything like that. He cited the fact that a capricornis he had given me was green but in my tank it is a tan color. He went on to say that most corals when exposed to light, adapt to the intensity. This will usually result in darker to lighter colors based on that intensity. In the case of this capricornis, it went from a green to tan. He said I could take that cap and move it down to the bottom of my tank and the color will be restored to green. Then he went on by saying that spectrum and even brand of bulb has more to do with color. I always thought that when people were talking about 10k, 12k, 20k, that they were referring to the amount of blue they wanted to see in their tank for visual purposes. He said that was only partly true. He said that the spectrum has a direct effect on the coral color. Not just what we see but how the coral changes. To make it more confusing, a 10k in one bulb can do something different then a 10k in another bulb. He suggested that I try changing one bulb at a time. Testing different brands until I find one that works well with my coral. He said the only reason that more people use SE then DE was because there is a huge difference in the number of bulbs available for one then the other.

So how much of what you have just read do you believe? Fact or fiction? It sure made me stop in my tracks before buying anymore darned equipment.

RichConley
09/05/2006, 01:52 PM
Some true, some false. Higher kelvin bulbs WILL make your corals look differnt, that doesnt mean they are different. (FWIW, your average 10K bulb has more blue/violet in it than your average 20k, the 20K just has a lot less yellow/green/red)

If things are turning tan in your tank, I'd look at nutrient levels before I looked at light.

sir_dudeguy
09/05/2006, 02:13 PM
ya i agree...partly true partley false...the color of the bulb (10K, 12K whatever..) wont nessesarilly change the color of the coral, but it will make it APPEAR a different color depending on what light you've got. For example I've only got a 4x96 pc retro on my 55. I've got a friend who gave me some zoo's...he's got the 20k mh bulbs and everything, and in his tank, the corals looked a lot more purple than they do in my tank, but they're still growing the same.

If the coral is turning tan tho, like rich said...check your levels...everything. Could be stress, could be sg, could be anything. But it may not be the light...what light do you have over how big of tank and where is this coral placed? I ask where its placed because obviously if its down lower it wont be getting as much light as it would up higher.

Wiskey
09/05/2006, 02:34 PM
<a href=showthread.php?s=&postid=8083113#post8083113 target=_blank>Originally posted</a> by RichConley
Higher kelvin bulbs WILL make your corals look differnt, that doesnt mean they are different.

:thumbsup:


If things are turning tan in your tank, I'd look at nutrient levels before I looked at light.

:thumbsup: :thumbsup:

I agree.
Whiskey

johnnstacy
09/05/2006, 02:43 PM
I have plenty of corals that are not brown. Most in fact are not brown. This cap I was talking about went from green to tan. A kind of yellow tan. Not brown at all. It's color shift is based on light intensity. Now I do have a couple of wild colonies I bought based on beautiful picture on websites and of course they arrived brown and have never changed but that is a different kind of thing.
The main issue for me is whether I really need to spend another $1000 on a 400W SE lighting setup or will sticking with my 250W DE HQI system work just as well.
While I can't speak to organic phosphates because I have yet to find a way to test for them, I have zero on nitrates and PO4 with the salifert tests. If anything, I probably have a nutrient poor envionment. I'm running a deltec 702 which is rated for something like 500g on my 180g tank. All of my parameters are fine.

Cal 400
Alk 8.5
PH 8.5
Temp 78.5-80
SG 1.026
Nit 0
PO4 0
Mag 1310

What can I say. I just see a lot of eye popping colors in many tanks but I don't have them in mine. .......

RichConley
09/05/2006, 02:50 PM
on a 180, 250s are MORE than enough. You could probably run it on a pair of 250SEs on lumenarcs.

I didnt notice the BB and big skimmer thing. Sounds like coral lightening to me. (green ot yellow)


Move it down like the LFS guy said.

MCary
09/05/2006, 04:24 PM
I don't want to be contrary, but I kind of agree with him more than the rest of you guys. I believe the intensity of the light needs to be adequate but beyond that probably doesn't change color. It may affect growth rate. Not really sure. I believe 10k bulbs color up corals more than 20k, not just in appearance.

Mike

FelipeBastos
09/05/2006, 06:43 PM
<a href=showthread.php?s=&postid=8083488#post8083488 target=_blank>Originally posted</a> by johnnstacy
I have plenty of corals that are not brown. Most in fact are not brown. This cap I was talking about went from green to tan. A kind of yellow tan. Not brown at all.

John,

How long did it take, from when you got the green cap until it appeared brown?

This would help understand the whole situation.

Felipe

johnnstacy
09/05/2006, 08:30 PM
<a href=showthread.php?s=&postid=8085049#post8085049 target=_blank>Originally posted</a> by FelipeBastos
John,

How long did it take, from when you got the green cap until it appeared brown?

This would help understand the whole situation.

Felipe

It was probably about 5 days. And let me explain. I bought this cap about a year ago and it was green. Then it went tan in my tank. Then when I moved, I had a big rubbermaid 150g tub with all of my rock and corals in it. I had the MH set up over it but many of the corals including the cap were sheltered. When I went to put the corals in the tank at the new house I noticed that the cap had some green to it again. Now the cap of course has reverted back to tank. The LFS said move it down and it will get green again. In fact, he said that most caps can do just fine under VHO.

wayne in norway
09/06/2006, 02:02 AM
Do you think SE 400's will output significantly more light than DE 250's?
You might consider, considering that you are dropping quite a lot of cash on lighting and bulbs, buying a PAR meter or at least a LUX meter so you can at least start to measure what you're spending hundreds of dollars on, rather than guessing on what you 'think' looks brighter..

And yes one manufacturers 10K can look very different to another mans, and even more so when you start swapping ballasts around. It is not easy to guess this.

silverwolf72
09/06/2006, 02:13 AM
ok my 2 cents just for fun but sounds like green color is the color of the coral while the tan color your seeing is due to more alge( Zooxanthellae sp)growing in the coral hidding the green color