blue light special anyone?

[clay]

well, after purchasing 2 compact bulbs from the lfs, and after finding out the bulbs were both 10000 k 50/50s that are now on my 30g planted tank, a question is now being posed. how do red plants react to more blue spectrum lighting? right now my Nymphaea stellata v. "versicolor and the Ludwigia repens x "palustris" are doing great. but my Alternanthera reineckii and the Ludwigia arcuata are not. could it have anything to do with the blue light?

i am dosing with excel everyday until i reset up my diy co2, and the other parameters seem to be where they need to be.

thanks!

[GDominy]

Well the actinic light isnt doing anything to benefit your plants really... so essentially you have the equivalent of a single 10000k bulb, not the two that you had intended to buy.

Actinic Blue light (430nm) is really below the usable range for plants... It does make stuff look really pretty but thats about it.

[2la]

Originally Posted by GDominy

Well the actinic light isnt doing anything to benefit your plants really... so essentially you have the equivalent of a single 10000k bulb, not the two that you had intended to buy.

Actinic Blue light (430nm) is really below the usable range for plants... It does make stuff look really pretty but thats about it.

Chlorophyll a's absorption spectrum peaks strongly right at (or very near) 430nm. While better lighting options exist, to say that the actinic light isn't doing anything of benefit is a bit of an exaggeration.

[clay]

well, that raises a good question, b/c i have had to do quite a lot of pruning, and my plants are not looking leggy at all. i personally am not a big fan of the look, but i wonder if higher light plants will like it. i am running about 3.5 wpg.

[rkundla]

Originally Posted by clay

well, after purchasing 2 compact bulbs from the lfs, and after finding out the bulbs were both 10000 k 50/50s that are now on my 30g planted tank, a question is now being posed. how do red plants react to more blue spectrum lighting? right now my Nymphaea stellata v. "versicolor and the Ludwigia repens x "palustris" are doing great. but my Alternanthera reineckii and the Ludwigia arcuata are not. could it have anything to do with the blue light?

When a plant looks 'green' to us, it is absorbing all colors but green. A red plant absorbs all colors but the red ones.

When something like Alternanthera reineckii turns more red, you would think that it needs more light enegy at the other end of the spectrum to keep it going.

Actually, this is an interesting question... does the color shift of a plant change its lighting requirements? Do red plants thrive better in 8800/10000K light (of high enough intensity) versus 5000K light?

Ron