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T5 Colormax Bulb

4596 Views 20 Replies 5 Participants Last post by  crazy loaches
Should I replace the Colormax T5 bulb with a standard 6700K for optimal plant growth, or will the Colormax do just as god of a job as the 6700K in terms of plants?

This is the fixture

Im using this in combination with this fixture all on a 75cm ADA

I also don't particularly like the color of the colormax, ironic eh? Its almost redish or purple...

Thanks guys
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should I replace the colormax with a 6700K, or 10,000K, because I've decided I really don't like the pink hue

I have 2x65 PC 6700K
and one 6700K 18w T5 and one colormax T5

My question here is, should I replace the colormax with a 6700K or 10,000K?

Im going for an ADA look btw
Well at the time I thought that was the safest bet for giving the guy advice, I'm not sure what my personal preference would be though. Generally I hear people saying that when giving advice, so I just passed on the word of people who had more experience than I. As well as the fact that it would stand out like a sore thumb, or at least I assume it would because it would be a 3:1 ratio of 6700K's :to: 10,000K's, and I'm sticking with the Coralife 6700K's cause I love em, and why get rid of a perfectly good 6700K T5 to replace it and the Colormax with two 10,000K's? Spypet, you have far more experience than I, if you were in the situation what would you do? Buy two 10,000K's, or just one more 6700K?

Oh and btw, I'm freaking out, my 75P just came like 45 min ago!!!!!!!!!!!!! :hihi:

of the threads I've read on this topic arrive at the following consensus:
most people seem to enjoy a mix of bulb colors, then just any one color.
I actually like having 3 colors on all my tanks; Colormax, 6700k, 10000k,
but if I'm stuck with only 2 bulbs to populate, I would go 6700k+10000k,
simply because Colormax lacks too much usable light for photosynthesis.

for the purpose of this discussion, my 8800k is close enough to 10000k
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So basically I should go with the 10,000K? sorry if I'm asking the same question over and over....

I thought before it would be better to have them mtch color, but I'm really not sure. I want uniformity throughout the colors and the fixtures are decently spread apart.
BTW, where do you get the 65w 8800K, thats the color that ADA uses, it must be nice
Spypet, I like your choice in bulbs! The slightly higher temps work great for deeper tanks and the colormax makes the colors stand out. Personaly, if I were to replace my bulbs, I would go with a dual daylight (6700 & 10000) and a colormax daylight (6700 & colormax). I loved the colormax on my 65w but it was just too much at 50%. 25% would be so much better. Another 3 months or so...
eh w/e, I just ordered the 6700K, I want everything uniform. let the thread die ppl
I would go with a dual daylight (6700 & 10000) and a colormax daylight (6700 & colormax).
If I were to buy new bulbs now, I'd do likewise.
In my case, I purchased my fixtures reconditioned
in order to save about 33% off their regular price.
The reseller saved me even more by including those
8800k bulbs which at the time were pretty cheap
because the company making them went out of
business. so for each fixture I bought 2 colormax
6700k, and now have a spare 8800k & colormax/67
on the shelf when it comes time for replacement.
Just my luck, Coralife was bought out, and those
colormax/67 square pin bulbs are impossible to find,
so it's just dumb luck I was "forced" to stock up :hihi:
I love the color rendition in my tank, it's just a shame
I don't have a camera yet worthy to document it all.
my Ludwigia Guinea look like they are on fire with all
these mixed up light colors.
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Last I looked at the Colormax packaging their little spectral graph (if at all correct) showed a much broader spectral distribution, more of wich is in the photosynthetic range as compared to a typical ~6500K where a lot of spectral radiance is in the green range and does little for plants just makes it look much brighter to our eyes. I'm not sure how thruroughly colormaxes have been used with plants, I was going to attempt but my bulb burnt out after just a couple months and I didnt replace.
Here's some color spectrums for some PC's.

Coralife 6700K

Coralife Colormax

ADA 8000K

Current Dual Daylight 6700K/10,000K

Light absorbsotion showing the wavelengths of some of the different pigments in plants
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Thanks LeftC... I actually tried to look on google and couldnt find the colormax graph. I might have to steal it from you for future reference. :icon_wink
Hi crazy loaches

You're very welcome to use these pics.

Left C

PS: Here's another one that might help too.

Left C
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I knew the colormax was somewhat usable. That was wonderful info!
My pic are from PC's. I hope that the T5's aren't very much different.
I've actually got tons of spectral graphs saved on my webserver, like the anacharis one and light absorbsotion one, just didnt have the colormax. I have actually posted those myself many-a-time. :icon_wink
lol, Left C. PCs are T5s, only "folded".
lol, Left C. PCs are T5s, only "folded".
Not exactly. PC's are fluorescents... so are T5's, T12, etc.

Average PC's in the 55W range use T5 sized tubes. But some larger PC's use T6, some smaller PC's use T4, etc, etc. What sets the spectrum is the phosphors, a T12 and a PC could have identical spectrums, the 'size' doesnt really matter.
"Im not sure... I know you can use an icecap ballast to power almost anything. I know that PC's are just T5's folded in half. Bulb diameter and 2 pins on either side are the same. Maybe I should just get an endcap..."

"The 5 in T-5 stands for the bulb size, and basically it is the same diameter as a PC bulb, except it is simply one straight tube. A PC bulb is one bulb folded in half, with a socket at the end"

"One more time. A T5 and a PC are the same animal. The PC is just bent or folded."

Your average Power Compact bulb (36w, 55w, 65w, & 96w) is T5 indicating it's diameter. Even some of the much smaller bulbs are also T5. Look at Coralife's UV lamps, also T5. While researching this, I have found that this bulb size is very popular in multiple-bulb and bent-bulb designs.
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