10k growth, 14k colour, is it cheating?

[fencer]

You could add actinics. If you are feeding your corals why don't you just keep the 14k on.

[digital-audiophile]

Tough to say if the growth can be attributed directly to the light temperature, no? Would you not have to to consider the vortech random flow and zeovit as well?

[Delphinus]

It's not just Kelvin temperature though is it? Well, partially I suppose. But going from 14k 150W to 10K 250W is surely going to have a pretty significant increase in PAR, you'd think?

[kwirky]

I basically put the findings from two different research papers on advanced aquarist together. The one paper had results that showed colour temperature played little role in SPS growth and instead PAR made a difference. The other paper showed that coral grown under 10k lights don't "lack" any colour and colour shows instantly when put under 20k bulbs. They did speculate that there's a possibility for certain colour proteins to only show up under certain colour temperatures or other variables but they said research has to be done to prove that.

There's a LOT of exciting research happening lately in coral colour
here are the two articles:
http://www.advancedaquarist.com/2008/3/aafeature1
http://www.advancedaquarist.com/2002...searchterm=PAR

Originally Posted by Delphinus

It's not just Kelvin temperature though is it? Well, partially I suppose. But going from 14k 150W to 10K 250W is surely going to have a pretty significant increase in PAR, you'd think?

the difference in ppfd according to sanjay's site is as follows (i substituted the icecap ballast for my galaxy and the M81 for the coralife HQI). almost 3x the PAR and I think that's why the monti frag bleached after coming from a medium light T5 system.

[Aquattro]

Well, years back many people would add the 250w Iwasaki bulbs, which were something like 7800K, but PAR through the roof and people saw amazing growth. 10k would certainly give faster growth than 14k, simply due to PAR levels. Lots of other factors too, but I've used both 10 and 14k, and 10k always produced more growth in the same tank.

[kwirky]

Originally Posted by fencer

You could add actinics. If you are feeding your corals why don't you just keep the 14k on.

no actinics for a while because of the budget restraints. and I'm running the XM bulb because I actually like the "shallow reef" look of it and the 150W 14k looks kinda dark. in the end I want to run a 10k bulb with fiji purple and super actinic T5's. that'll happen as the money happens.

and I don't feed my corals beyond zeovit, amino acids, and coral vitalizer. if it were to be considered scientifically there are too many variables to really figure out if any one thing is contributing more than another. I don't know if the amino acids or the CV is helping but I dose it anyways. I don't want to start turning anything down or removing anything out of fear of stopping the momentum

i got the little frags to see when the tank's ready for larger more expensive coral. 3 frags included 2 acropora types and one red monti (not the superman). the red monti bleached and the 2 acropora are doing well. so I'm not getting more for a while unless I see the monti reverse in health.