T5 or VHO for supplemental lighting?

[The R/C Man]

Here is the deal...

30" tall tank
4 x 400W MH 20K bulbs for the main lighting
The T5's = 192watts
The VHO's = 600watts
With the MH's I am thinking I am covered as far as PAR goes.
I am making the consideration based on the corals needs vs my wallet.
Now should I add 8, T5 bulbs or 8, VHO's to supplement?
If you all think the SPS will need the lighting I will suck up the power bill. If not I will go with the T5 strictly to balance out the 20k's.....

[Poseidon]

Are you supplementing WHITE because the 20K's are too blue?

If so I would do T5 no question. If you are adding more actinic, VHO is still the best, but D+D True actinic T5 is pretty darn close, and half the wattage.

[The R/C Man]

Yeah I am planning to use 6k or a combo of 6 and 10k T5's.

My little tank has a 250W MH 20k supplemented with 6700k PCs and looks the same as a 10k MH with actinic PC's. I figured I may as well get the power to the corals from the 20K spektrum...

[Poseidon]

If that is the case, then T5 all the way!

[corrado007]

Hey guys, I'm not trying to hijack your thread but I'm very curious about supplimental lighting as well and trying to learn its purpose(I've only got 4x65w PCs now). Is supplimental lighting usually just to get the visible color you want, that is, to bring out the color in the corals/make them glow? Don't you get all the PAR you need from the MH lamps?
Thanks

[charlie]

Lots of folks just use them for aesthetics, or the dawn-dusk effect.

[corrado007]

I see. So if you were to use a 14k bulb there would likely be no real need for the supplemental lighting (colorwise) except perhpas if you wished to ease your animals into more intense MH lighting with the dawn/dusk less intense lighting. That makes sense.
Thanks

[The R/C Man]

Thats correct. I have decided to go with 20K MH bulbs for the main lighting. Having the higher wattage at the spectrum that penetrates the water deepest makes more sense to me. Since that will ultimately make the tank appear bluish and not very bright to our eyes I choose to add the other colors of the spetrum to balance it out.

[charlie]

I supplemented 6 400w 20K radiums. with 6 various wattage, VHO actinics, and had some really good growth going on. I think R/C man can attest to that.
I think the dawn to dusk effect is for human eyes only.

[The R/C Man]

Hey Charlie!

Yeah I am not sure if the dusk to dawn effect matters or not. It is however a possibility. I do believe it helps from freaking out the fish when the lights just all of the sudden come on though. Hopefully it will be a good look and provide adequate lighting for the corals.

[Poseidon]

I like the dawn/dusk effect myself, and as an anecdotal evidence, my Blue tort has really colored up since adding the 5th bulb. (I am sure it has more to do with the added light, then the dusk/dawn though.)

[corrado007]

How many T-5s would you need to replace a VHO. Lets say you had 2x 48" 110W VHO actinic bulbs as supplementation to a pair of 10k MH lamps, would you only need 2x 54W T-5s to achieve the same effect?

[Poseidon]

Yup, 2x54W will be fine.