should i use one 10k and one 14k mh bulb? Need fast answer!

[grom]

Right now I have 2x175w 10k mh with 2x39w 10k and 2x39w super actinic.
I want a whiter light, but to still have some blue.
With this setup, i dont have enough blue, and id like to add more.

should i replace the 2x39w 10k with another set of 2x39w super actinic?

Or should I replace one mh with a 175w 14k mh. (would this make one side of the tank blue, and the other white? Or would light spread out evenly and you could barely tell?)

All of this is in one fixture, 8 inches from the water line.

[Grassroots]

replacing the 2 bulbs with super actinics would be the better of those 2 options... The second option wouldnt work.

[Reef 101]

14000K metal halide bulb offers excellent coloration and good intensity. It is crisp-white with a blue tint. It brings out the fluorescent pigments in corals nicely. Fluorescent supplementation is usually not necessary, but can be used for added intensity and to simulate dawn and dusk. An excellent choice for reef tanks 24" or deeper. on how the different Kelvin ratings appear and more information on metal halide bulbs. You get a better color overall.

[grom]

I tried the dual 14k with 2x39w 10k and 2x39w super actinic
way too much blue

i think ill just do 2x 10k mh with 4x superactinic t5ho


do the super actinic do anything though? or is it just for looks?

[Reef 101]

super actinic penitrate it deepier

[grom]

deep penetration is good

[j0tca]

You might try giving the 14Ks more than a couple minutes try. The first time I used 14K I thought the tank looked way too blue but after a couple days I really began to appreciate the extra brilliance that the blue light brought out in the tank.

As to actual benefit, frankly all your lighting options are roughly equivalent. Blue light penetrates deeper but unless you've got a very deep tank it really doesn't make much of a real difference IMO. It's mostly a matter of total wattage of light and appearance.

[grom]

tank is only 21 inches high
light fixture is 7.5 inches from water line. Its as high as it goes.

Should I lower it? I plan on having 2 lta (sandbed) and 2 clams (one derasa on sandbed, one ultra maxima somewhere on rocks)


I tried mh 14k with 4 super actinic for 2 weeks, I always hated the color. It made everything look very fake and plastic :P

I wish i could try 14k mh with 4x t5ho 10k :P
I wonder which would look better. But im mostly going for growth and natural coloring so thats why im going with mh 10k with actinic t5ho.

[j0tca]

With the 2 175W bulbs you have enough light in the tank. I know there are people who say that they see big increases in growth rates after changing bulbs but frankly, in the vast majority of tanks, enough light is simply enough light and the rest is looks (IMO).

A 21" tank isn't deep enough for the blue light to make that much of a difference over 10K. The attenuation of even red light (first to go) is very little in 21" of water.

I remember the color combination on the tank that was using 14Ks that I really liked the best was a lighting cycle like

7:00 am 2X65W Super actinic (VHO) come on
8:00 am 2X250W 14K come on
10:00 am 2X 110W 10K (VHO) come on

I thought the mix of white VHOs and 14K halides was pretty good and having them come on in sequence really gave it a "waking" up feeling at the begging (and end) of the day.

My only real advice is don't think anything really will affect the success of your tank, your lighting choices are all good and it just comes down to what you prefer.

You may end up placing the clams right under the MHs but I've seen very happy and successful clams under half of the light you have on the tank.

[grom]

I heard to maybe try ati blue+ bulbs. 4 of those with my 10k mh

is it really worth it to switch from one actinic bulb to the other?
I just want my colors on corals/anemones/clams to stick out more. I have a coral that looked neon green in store, and looks yellow (no green at all) in my tank. I switched to 4 actinic bulbs, and it barely made a difference...I dont know what to do =/

[grom]

still need advice =/

[Gawain1974]

What type of corals are you keeping, and what type of growth are you interested in? If you want faster growth and are keeping SPS, I'd stick with the 10K halides and switch out your actinics. If you're more interested in coloration and slower growth, then switch out the halides. When I ran 175 watt halides, I used the 13K AB bulbs because their PAR output was similar to other 10K bulbs on the market, and there was more of a blue hint to their colors. Coupled with my actinics, it was a nice blue look.