20K Halides vs actinics

[RockDoc]

Hi all,
If 20K halides are so much more blue than 10K, do they replace actinics for coral coloration? In other words, if I build a frag tank and put 20K halides over it, do I still need to get actual actinic bulbs in addition? Thoughts are appreciated.
Thanks as usual,
Jay

[Phurst]

Actinics in this situation would be purely up to your aesthetic preference IMO. I ran 2 20k HQI bulbs and 2 actininc PC bulbs for a while, but it was a little too blue for my taste.

[RockDoc]

up to your aesthetic preference. . .
Thanks for the quick reply. Does this mean that as far as the health and coloration of the corals is concerned, 20K halides alone are sufficient? The actinics are not necessary for the actual coral health?

[Phurst]

I found that coloration was excelent under the 20Ks alone. Aditional actinics may cause slightly more "flourescence", but coloration will be fine without them. Again, IMO.

[Mr. Tang]

I have been using 2 250 watt 20,000 MH's and also 220 watts vho actinics. I hoped that the mh's would be blue enough but was'nt happy with them. I also like to be able to turn on the actinics on an hour before the mh's come on. I don't think the actinics help any corals grow better but I do like the way they cause the colors to pop when just the actinics are on alone.
I wonder if different brand mh bulbs at 20,000 have different shades of blue??

[CarmieJo]

I thought that you actually got more growth under lower K bulbs...

[Phurst]

I thought that you actually got more growth under lower K bulbs...

Yep, for the most part that's true. Better coloration with the higher k bulbs.

[CarmieJo]

But the color is because it is what we like to look at not if the coral is healthy, right?

[lReef lKeeper]

VERY controversial subject ... basicly 10K = great par, 20K = fair par, 14k & 15K = low par.

10K is great for coral growth
20K is great for coloration
IMO, 14K & 15K great for being worthless

this is only for halides.

for the best of both worlds ... growth AND coloration here is what i would recommend ...

10K Coralview Reeflux bulbs on electronic ballasts. the bulbs have a more blue tint to them for coloration AND the par of a XM 10K for growth. with 2 x 110w VHO reeftinic supplemental actinics.

[Pescaiolo]

I have seen people using just 20k bulbs and getting great color. I guess its more of a matter of preference.

[JasonR]

[QUOTE=IMO, 14K & 15K great for being worthless[/QUOTE]

Just curious, why do you say that? I run a 14K 250 HQI and 2 -65w power compact actinic 03's
The halides are driven with an electronic ballast.

would i be better off with a 20k MH and 10K 65 watt pc's?

[lReef lKeeper]

Just curious, why do you say that? I run a 14K 250 HQI and 2 -65w power compact actinic 03's
The halides are driven with an electronic ballast.

would i be better off with a 20k MH and 10K 65 watt pc's?

just because ... most 14k and 15k rated bulbs have LESS par than a 20k (epspecially the XM 15k's). low par means less coral growth and higher coral placement in most cases.

you actually WOULD be better off (in the par area) with 20k bulbs. what brand of bulbs are you using ?? i always recommend Reeflux bulbs, because they are the top of the line bulbs available to us today, IMHO. check out this link that Rob provided in the show notes of one of the live shows ...

250Watt Bulb Comparison (http://chrismorris.ca/250wcolour/)

you can change the bulbs on each half of the tank to see the difference in color WITHOUT actinics. check out the blue of the 250 10k Reeflux compared to the other 10k bulbs he tried out.