I am not sure if you would want to go with 3000k or 3500k spectrum lights, I think the lowest you want to go is around 4000k. If I remember correctly the ideal spectrum are between 4500k and 6700k, and then if you can water over 18 inches deep you need some 10,000k to help penetrate. Hopefully someone else will comment on this, because now I am curious to know.
Aquarium lighting has really 2 opposing light issues 1)whats good for plants and 2)what is good for your "taste"
A fairly ideal spectrum fulfilling both criteria:
BML Dutch planted
As to light attenuation, see bottom row:
This gives you an idea of the spectrum lost ..The above chart was generated from a "custom" spectrum, higher in blue than the Dutch..you lose mostly red to deep red.. w/ all other colors being unaffected really (well proportionally decreased).
"K" values are for viewing..but low K LED's have more red generating phosphor..
As you can see from this (Cree color families):
Warm white LED's have close to 2x the important deep red band than cool white..
10000K are unnecessary w/ enough "average" whites. i.e 7000-5500K
attenuation of 6500K(10) 660nm red(3) cyan(2)