I have a current brand light that holds 2 combo bulbs. I currently have a dual actinic (420 & 460) and a dual daylight (10,000K). The daylight needs to be changed. When I went to the pet store that i buy my supplies from (that I even bought this light from) they said they are no longer carrying the 10,000K daylight bulbs. He suggested I put in 2 50/50 (blue and daylight).

My question is what's the benefit of getting rid of the red for an additional blue?

I understand that blue penetrates the water better, however, I thought the red part of the dual actinic was suppose to be a spectrum that isn't visible to the human eye but is beneficial to the fish.

IDK anything about red lighting. But i have a 12g aqua-pod and it has 1-27W square pin Dual Daylight 6700°K/10000°K Daylight bulb, 1-27W square pin Dual Actinic 420nm/460nm Actinic bulb, 2 blue LED lights, one of them is the blue bulb and it works fine, but i have never used red bulbs for a reef tank, or any fish for that matter

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Glad to be of any help-Austin.

First off what is the wattage of the bulbs and are they straight pin or square pin. Where are you getting the red light from 10k's should be a crisp white with most of the wave lengths in the yellow to blue range I believe. I like running daylights and actincs but not 50/50 bulbs because it gives you better dawn and dusk lighting at least IMO

96k for all 4, square pin

I call it red, but that's just my generic way of differentiating the bulbs. The 'red' is the second half of the dual actinic (420) so when it's lit up it doesn't give off much visible light, but if you look at it next to the blue it has a red/pink tint to it. It's the way the dual actinics I buy have always been, and I was under the impression that the 'red/invisible' light was important to fish and invertebrates. But if that's the case I don't understand why my supplier would no longer want to carry them. It would seem by switching to all white and blue (10,000K daylight & 460nm actinic) the environment would be lacking beneficial light.