So what's the general rule for colours as I haven't been able to find any info regarding the ratio between white leds and blues/reds etc. I don't want to over do it and get a horrible colour in the tank I want it as close to 6500k as possible so it looks pretty natural.
Look at it this way.. say you ran 10 10000k whites on one channel
10 3000k whites on another
For the sake of simplicity assume they are looked at as equal in your eyes..
So when all are at "full" your CCT is 13000/2 =6500k
IF you shut the 3000k channel off you get a 10000k tank (at 1/2 luminosity of course)
now add colors for 2 reasons 1)add specific PAR regions and 2)broaden or flatten the spectrum
As you saw all "white" are not really white but a blue LED plus yellow phosphor giving an uneven spread..
WW and cool whites together help "flatten" the curves and in general are really all that is (in my mind and many opinions) necessary.. See how the warm white "fills in" a lot of the lower red area and has less blue.. Averaging those 2 curves will give you a flatter spectrum.. w/ one teeny exception, the 475ish region.. (this is where cyan LEDs come in but it is not perfect either. The "kicker" though is it punches up greens and you eye really likes green so it appears very "vivid", A WORD of caution.. some "cyan" leds are just a blue and yellow LED combined and DO NOT peak or fill the same way, though they "look" similar)
Throwing red (deep red 660nm) and royal blue (470nm) just add PAR "punch" so to speak..
Either running a seperate channel (recommended) or only modest use of them is recommended.
Interesting collection of "chatter" re this.
One not of caution: You must decide what "white" you like.. ignoring the 6500k aspect for now, and as I found out.. the warmer leds are more "visually warm" than the coll ones are "visually blue" if that makes any sense.
In other words if you like a crisp white look yet want a warmer fill (sunset dimming, just a bit of red pop) you wouldn't do 50/50 ww/cw but somewhere a bit lower.. say 2/1 ratio cw/ww. Again though, dimming is your friend.
BUT you also want to max. your output.
Gets tricky.. and to be honest,
I haven't even completely decided myself..I've had "just" 3500k and "just 6500K and now 50/50 3500k/6500k as "main lighting" and haven't decided which is a favorite.. The fill colors add "pop" to every fish color and plants are marvelously green but the overall tone, though FAR from bad.. well I'm just not sure.
Of course I broke my own recommendation by running a combined ww/cw channel instead of a seperate channel, thinking I was smarter than myself.....
Of course replacement LED's would be no problem..