6700k or 18000k

[jorjef]

The facts

I know 6700K is more in line for fresh water planted tanks but is there going to be that much of a difference compared to 18000K based on the following


20" water depth
Lps and softies

I have run only the 18000k bulbs from the start but wondered what I will loose buy going to 6700K. Also any benefit in running a combination of the two or stick to one or the other.

[lastlight]

you will lose any hint of blue you may have ever liked! That will be super yellow...but bright as hell I imagine. This metal halide?

[jorjef]

Oops I guess I didn't give all the facts... It's T-5 Hagen lights which I'm stuck with. Unless I can find other 22" bulbs. The choices are 6700K, 18000K or actinic which seem way too blue.

[lastlight]

Well the colour comment still applies...not sure how PAR is affected with those bulbs.

[bumper]

Any t5 HO 24W are ~22", Bayside would have them in a 14000K or close. Pair up a blue (actinic) and daylight (14000K) lamp. You may find you have an algae issue with any 6700K. Would be great for macros though.

[abcha0s]

Mix the bulbs. One of each.

If you can only have one bulb, I'd go with the 18K.

[gobytron]

euphyllia and lps really like the blue spectrum from what I have read...

plus, an 18k bulb is much less likely to promote problematic algae growth.



If it were me, I'd do a mix of them if possible and go from there.

[jorjef]

Any t5 HO 24W are ~22", Bayside would have them in a 14000K or close. Pair up a blue (actinic) and daylight (14000K) lamp. You may find you have an algae issue with any 6700K. Would be great for macros though.


I will have to give them a call, from what i've read 14000K seems to be the bulb of choice vs. the 18000K. I know the benefits of actinic but when I tried one with a 18000K the tank seems too dark.

[Lance]

If it was my tank I'd go with 2x 14000K.