Actinics?

[Mik_101]

Hi all I'm just wondering if its recommended to use actinics on a tank. I might be starting up a 108 gallon if i get it from reefaddict29er. I'm planing to use 2x 250 w SE mh at 14k. The tank will be mixed reef sps,lps and softies along with clams.

[Myka]

You will probably want to run actinics. It provides a spectrum of lighting that is required for photosynthesis. Full pectrum bulbs will also provide this, but you may want actinics purely for the color. Actinic (expecially if you use pure true actinic bulbs) will make corals fluoresce, and intensify all colors.

[digital-audiophile]

IMHO actinics are nice for dawn and dusk cycles. But at least with my lights once the halides come on, you can turn the actinics on or off and they make no difference in light or colour as they are being drowned out by the MH.

[PoonTang]

With 14k Mh you dont need Actinics, its already in the spectrum. Check here, http://www.aquariumpros.ca/forums/sh...ad.php?t=17248

[fkshiu]

Actinics give you more flexibility. You can run dawn/dusk cycles, but more importantly, you can run a lower kelvin MH bulb to get the benefit of its higher PAR value by offsetting the overly yellow colour you get with actinics. I disagree that MH will drown out actinics. I run XM 10K MH bulbs which are quite yellow. When I turn on my T5 Actinic+ and the VHO UVL Superactinics, the colour is balanced out to a nice clear white.

[Samw]

In the past, I have measured the dissolved oxygen level of my water with no lighting and then with only 96W of actinic light for an hour and the oxygen meter showed a 0% increase in oxygen. However, as soon as I turned on my regular PC bulb or my MH bulb, oxygen levels increased significantly within the hour. If the byproduct of photosynthesis is oxygen, then one might conclude that a 96W actinic PC bulb resulted in little or no photosynthesis.

[mark]

Actinics are for your benefit, not the coral and the fish.

Currently have actinics only (2x54W T5) along with 2x250W 14k Hamilton's and things definitely fluoresce, even with the MH on.

One thing though, before I had the T5s ran 2x40W NO fluorescents (one 50/50 other actinic) for dusk/dawn. Do have to say, still prefer that combo of softer white light more than the purple glow of the actinics only with the MH off. I've got another T5 set with 10k (2x54W) yet to put in, though thinking even a smaller CF might be enough to get some white back into the mix. Wouldn't want to give up the effect I get with the 2 T5 actinic though.

[Mik_101]

danm i cant have the tank because of space issues