mhucasey...just finished reading the last 50 pages or so of this thread and I want to say thank you very much for all the time you spend answering questions!! (Thanks to TropTrea as well) I have a couple of questions:
1. a few pages back you seemed to have settled on the bulb combo above. Shortly after you started your second tank and never really mentioned how this combo worked long term for growth/coloration. I really like the color from your pictures and am curious.
2. You mention you typically run one channel for 11.5 hours and your main channel for around 6.5 hours. I picked up a Pacific Sun Diuna which is an 8 bulb fixture and I can control 4 channels independently. Would this change your timing at all? Reason I ask is that all the acroporas are very happy but I have two monti's and a ponape birdnest that are fading. I currently run 1 channel for 8 hours (Actinic +, pure actinic) and the rest run for 5 hours. I am concerned about adding time to my schedule...
Front
Pac sun crystal blue
PS crystal blue
PS pigment INT
Actinic +
Pure actinic
PS pigment
PS Spectra
PS crystal blue
Back
First off, thanks very much for the kind words!
That combo worked very well for color and growth and I kept it for a decent amount of time(for me). The tweaks to the mix of bulbs I make are really more for my visual enjoyment then to find the magic mix that will make the corals grow.
After looking at a lot of threads and significantly different bulb mixes that resulted in great coral colors and growth, it became obvious to me that it comes down to how the lights make the corals look to you that is most important.
I also tried the two groups of four bulbs as an experiment(I rewired my fixture) and it didn't seem to affect the corals much in either a positive or negative way. I still stick to the 11.5 hour/6.5 hour photoperiod recommendation even if its the 4 bulbs that are on longest. Your montis and birdsnest corals could be just up a bit too high, or it could be a nutrient issue. I had montis getting well over 500 par with no issues so its too little to go on right now.
Now that I have two tanks and three fixtures, I have been trying to come up with a formula for the mix that I like(So I can hopefully stick to it long term and reproduce it easily). The general formula is that for every 8 bulbs, I want 2 Purple, 1-2 ABS and the rest blue. Swap out a blue or two with a New Gen or Aquablue Azure(neutral white) to make it brighter.
I tried the following on the 8 bulb fixture and really liked it for the LPS heavy tank: B+, Fiji Purple, Superblue, B+, ABS, B+, Fiji Purple, B+ It looks amazing on that tank and I don't want it any brighter. I then tried to reproduce the color mix, but a bit brighter using the two six-bulb fixtures on the other tank. After a lot of trial and error and the formula above, I think its pretty good now.
From one side to the other, the mix is as follows:
KZ new Gen, B+, Fiji purple, ABS, B+, Fiji Purple, Coral Light(Same as ABS), B+, B+, Fiji Purple, SuperBlue, KZ New Gen.
So 3 purple, 2 ABS-type, 2 neutral white, 5 Blue.
So for your Proposed mix,
You have 2 Purple bulbs(pigment int)
1 White bulb(Spectra, Like a coral plus)
One actinic
4 Blue
I think thats a good mix visually, the spectra has a little more red and a little less green than an ABS or Pacific Sun's "Shallow Water", but that is balanced by the addition of the actinic bulb, which adds some 420 nanometer and green, without adding more blue.
If you like the look I don't see any reason to change, there is a good representation of all the important parts of the spectrum and with that many bulbs your par will be plenty.