My SPS are either losing color or turning fluorescent green

I have been keeping SPS corals in my 150 gallon reef tank for a little
over two months since installing a 250 watt HQI minipendant with a 10K
bulb installed, using a icecap 250 Watt electonic ballast. The
distance from the middle of the bulb to the water surface is about 6
inches, with a UV shield preventing water splatters from bursting the
bulb. What I have been noticing is that the majority of my SPS corals
have either been losing their colors, or turning a fluorescent green
color. All the SPS that I have placed in the tank appear to be
healthy with good polyp extension, but once again the colors appear to
gradually fade. My nitrate and phosphate levels are zero. When I
first added SPS, I placed them high up in the tank within 10 inches of
the MH bulb, but virtually every single SPS appeared to begin to
bleach at this distance (this includes a brilliant blue A. tortusa
frag). When I noticed this bleaching, I moved the majority of frags
further down in the tank to about 16" from the bulb. This includes
the A. tortusa frag, which has made a great comeback and is now once
again a brilliant deep blue. Since I know that the A. tortusa frag is
considered one of the most light demanding species, I am guessing that
I need to move my other frags even lower in the tank. Further I am
wondering that perhaps changing my bulb to a 250W XDE 20,000K HQI may
help the coloration of the SPS. Any thoughts?

the 20KK bulbs IME give much better coloration but less growth.

regardless of the coral's light demands its always best to introduce them at
the bottom of the tank and slowly bring them up to the light.

hth
kc

"Timothy Tom" wrote in message
m...
I have been keeping SPS corals in my 150 gallon reef tank for a little
over two months since installing a 250 watt HQI minipendant with a 10K
bulb installed, using a icecap 250 Watt electonic ballast. The
distance from the middle of the bulb to the water surface is about 6
inches, with a UV shield preventing water splatters from bursting the
bulb. What I have been noticing is that the majority of my SPS corals
have either been losing their colors, or turning a fluorescent green
color. All the SPS that I have placed in the tank appear to be
healthy with good polyp extension, but once again the colors appear to
gradually fade. My nitrate and phosphate levels are zero. When I
first added SPS, I placed them high up in the tank within 10 inches of
the MH bulb, but virtually every single SPS appeared to begin to
bleach at this distance (this includes a brilliant blue A. tortusa
frag). When I noticed this bleaching, I moved the majority of frags
further down in the tank to about 16" from the bulb. This includes
the A. tortusa frag, which has made a great comeback and is now once
again a brilliant deep blue. Since I know that the A. tortusa frag is
considered one of the most light demanding species, I am guessing that
I need to move my other frags even lower in the tank. Further I am
wondering that perhaps changing my bulb to a 250W XDE 20,000K HQI may
help the coloration of the SPS. Any thoughts?

the 20KK bulbs IME give much better coloration but less growth.



True in some cases but not all.. I have found that many corals color best under
6500k iwasakis (coloration is better because of the MUCH higher PAR) and some
corals color better under 20000K radiums.. (Less par but higher Kelvin). here
is an example of a mille that has been under Iwasakis only(no actinic).. under
Radiums this coral was not half as colorful as it is under Iwasaki 6500k.
http://www.asplashoflife.com/magneta.gif
Rod Buehler
www.asplashoflife.com

i dont dought what you say, but i find it hard to belive that pic was taken
under a 6500K Iwasaki bulb, its to white. IME the Iwasaki's are very yellow
and that is why i will only use them on my growout tank and would NEVER use
one on a display tank.

kc

"Rod" wrote in message
...

the 20KK bulbs IME give much better coloration but less growth.



True in some cases but not all.. I have found that many corals color best
under
6500k iwasakis (coloration is better because of the MUCH higher PAR) and
some
corals color better under 20000K radiums.. (Less par but higher Kelvin).
here
is an example of a mille that has been under Iwasakis only(no actinic)..
under
Radiums this coral was not half as colorful as it is under Iwasaki 6500k.
http://www.asplashoflife.com/magneta.gif
Rod Buehler
www.asplashoflife.com

i dont dought what you say, but i find it hard to belive that pic was taken
under a 6500K Iwasaki bulb, its to white. IME the Iwasaki's are very yellow
and that is why i will only use them on my growout tank and would NEVER use
one on a display tank.

kc

You are more than welcome to come and see at any time even though "you dont
care what I say" . There are many people that can vouch for the bulbs we use. I
was just saying that its a BIG BLANKET STATMENT, to say that you will get
better coloration in ALL corals with Rradiunm bulbs.. That is completely BS..
Some corals, Yes.. But ALL ?? LOL. I must say that this is the first time I
have been called a liar on any of the boards . If you care to use the
unnatural blue look, that fine with me,(sometimes I like the look too) but I
like that natural daylight look. I dont see the yellow color.. I see nice
white..
Rod Buehler
www.asplashoflife.com

i just expressed my opinion of the pic, not your statments or trying to
discredit you. you jump to conclusions and think i was calling you a lier.
i was not. sorry you take it that way.

kc

"Rod" wrote in message
...
i dont dought what you say, but i find it hard to belive that pic was
taken
under a 6500K Iwasaki bulb, its to white. IME the Iwasaki's are very
yellow
and that is why i will only use them on my growout tank and would NEVER
use
one on a display tank.

kc

You are more than welcome to come and see at any time even though "you
dont
care what I say" . There are many people that can vouch for the bulbs we
use. I
was just saying that its a BIG BLANKET STATMENT, to say that you will get
better coloration in ALL corals with Rradiunm bulbs.. That is completely
BS..
Some corals, Yes.. But ALL ?? LOL. I must say that this is the first time
I
have been called a liar on any of the boards . If you care to use the
unnatural blue look, that fine with me,(sometimes I like the look too) but
I
like that natural daylight look. I dont see the yellow color.. I see nice
white..
Rod Buehler
www.asplashoflife.com

Further I am
wondering that perhaps changing my bulb to a 250W XDE 20,000K HQI may
help the coloration of the SPS. Any thoughts?

Read the end of this article ...
http://www.dynamicecomorphology.com/steveletermfm01.htm

And this full article ...
http://www.reefs.org/library/talklog...ee_060202.html

jc