Lighting question...

[elfloyd]

I currently run two 250w MH (20,000k) and two VHOs (Super Actinic) over my standard sized 90g tank. I am planning my tank upgrade and am wondering if I am overkilling the light spectrum.

For the new build (180-240g) am I OK just to add three 250w MH (20,000k), or do I need the actinic too? I guess the real question is what is the correct mix of MH and Actinic bulbs?

I want to have enough light for all coral varieties.

 

[jaustin]

There is no correct mix, it's what you like in the color....but think about adding one actinic 454, they are nice!

 

[brianjfinn]

I believe, as long as there is enough intensity, the color is only a matter of preference. Lower kelvin and less actinic gives more growth, while higher kelvin and more actinic gives more color. Depending on the depth of the tank, I would think that the metal halides alone would be enough to support most corals.

Someone correct me if I'm wrong...

 

[elfloyd]

brianjfinn;492840 wrote: ...Lower kelvin and less actinic gives more growth, while higher kelvin and more actinic gives more color...

Then the best of both worlds may be to lower the MH spectrum from 20k to 14k and keep the actinics. This would give more growth than I see now... but retain the higher color level.


Thoughts?

 

[weaglereefer]

Do you leave your actinics on when the halides are on, or just for sunrise/sunset? I can definitely tell a difference with my 2 actinic bulbs on vs. off even with my halides on. The purple coraline just glows when the actinics are on.

I've been meaning to try one of those 454 Actinic VHO's, just can't seem to find someone who stocks them in ATL, and most places online that have them want $25 for s/h alone, not to mention the cost of the bulb.

 

[elfloyd]

I start the actinic (30 & 60 minutes) before the MH come on, run them while the MH are on, and keep them going after the MH are off (30 & 60 minutes).

I've got two new Super Actinic ready for replacements, maybe I'll find the 454's before the build is complete.

 

[weaglereefer]

Then I can say that going to 14k will make a noticeable difference in the color of the tank. I would think running 20k halides AND VHO actinics would make for a psychadelic looking tank.

I would see if you can rent a PAR meter and get some numbers from the current halide bulbs, this will really tell you if you are getting "enough" light for stuff in your tank. How tall will the future tank be vs. your current tank? Are you happy with current growth? Are you happy with color?

 

[elfloyd]

au01st;492871 wrote: ...I would think running 20k halides AND VHO actinics would make for a psychadelic looking tank...

hmmm... never thought about it... maybe I do have a psychedelic look?

 

[brianjfinn]

I think it looks great the way it is. If you want more growth, then the 14k bulbs should help, but I love the bluer color. When I upgrade I'll be doing 20k metal halides with super actinic and 454 t5s

 

[jaustin]

With the right bulb/ballast/reflector combination you can get the same PAR out of a 20K as you can a 10K. It's all about the quality of the equipment. Research is your friend when it comes to metal halide bulb selection.