Lighting Comparison

[The R/C Man]

Hey Everyone!

Well as a test bed for my 375 gallon system I have decided to change the bulbs on my 25 gallon to see if I like the outcome or not....

I started out with a 250W Radium 10K MH supplimented by 2 65W Sunpac Actinic PC's. The left picture....

I have changed to a 250W 20K MH suplimented by 2 65W Sunpac 6700/10k PC's..... The right pcture..

The immediate noticable difference was in the tri-color acro. The tips appear much more of a reddish purple than the bluer/darker purple of the 10K and Actinic combo. I also noticed the pocillipora appears a darker pink and some minor differences in the other corals coloration. Overall however very similar. I am expecting a significant change in growth and coloration over time as the 20K spectrum will penetrate deeper than the actinic PCs did providing them more light..... More to follow.

[Poseidon]

Boy Greg those two combinations are VERY Close. It appears the one on the left is slightly "warmer" then the one on the right. But I really had to study both pictures. (I am also on my laptop so that may have something to do with it too.) I would think the opposite of what you stated though, about the penetration. I think the 10K is overall "brighter" then the 20K, even though blue light does penetrate the water deeper then the other parts of the spectrum. I just don't think that the depth of our tanks is enough to realize the difference, if the tank was 120" deep then yes, but not something that is only 24" or so...

[The R/C Man]

Yes very close indeed! I am hoping that the 20k will produce better colors. According to a presentation given by Steve Tyree that part of the spectrum is most beneficial to a majority of corals. With that said, more output (250W) as oppposed to the 130W PCs should be better. At least in theory anyway.

So far it seems to be visually brighter overall than the old bulb. Of course that bulb has been running for 12 months so that isn't a good comparison.

So far I like the combination and I think that is how the 375 will be lighted. The difference will be 400W MH and 24" VHO's instead of PC's. It should work great......

I post a couple larger pics for better comparison....

[charlie]

Greg,
Depending on how much blue you like, the 20k's will give you all of that, believe me, I know!!!! I think that the 10k you had on there almost looks crisper than the 20k, remember who this is coming from!!!!!
Have you tried that Coralvue 14K that Kevin has? I am running those on my 80, and they are really nice!!

[The R/C Man]

Here are a couple larger pics...

[The R/C Man]

Hey Charlie!

Yes, I seem to have more blue with the 10K and Actinic PCs. However I believe over time the corals will recieve more light and therefore benefit from the change. Only time will tell...

[charlie]

How long ago did you do the change Greg?

[The R/C Man]

Hey Charlie!

Did it this morning..... Why?

[charlie]

Just wondering
How did you adjust your photoperiod for acclimation?

[The R/C Man]

I thought about that but Kevin said not worry about it.... Do you think I should limit it a bit?

[Reefland]

I don't think I would worry about limiting it. I am not sure how the Radium 20k's compare but the AB 20k's that we were running had less punch (PAR) than some 175's on the market. I really enjoyed the coloration (they were pretty blue) but was not happy with the growth. We have since changed to 10k XM's and get a lot more punch from the lights and see better coral coloration (although this could be many other things).

The comparisons you have look good though!

[Poseidon]

Yup you are right Greg, the Tri Color Acro definately shows the most color change. I think I like the deep blue of the 10K myself. I guess time will tell what difference you get in Growth!

[The R/C Man]

Yeah I think the blue was actually brought out by the actinics. They where a duel spectrum at 420nm and 460nm. The new 6700/10 PC's are what bring out the purple. I may remove one of the 6700/10k PC's and put one of the actincs back in. That will cover a huge spread......

[The R/C Man]

Ok, I am trying one more thing. One of the daylight PC's were removed (back one) and replaced with an actinic. The tri-color is showing a true purple instead of siding towards red or blue. Overall the tank appears slightly dimmer to the eye and definitly leans towards blue. I am not sure if I like it or not. To much blue doesn't seem to give it the right balance.....

Here another pic with the 20k and 1 Daylight PC and 1 Actinic PC.