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brighteye
08/30/2008, 08:34 PM
Hi all,
I am coming back to marine after a decade hiatus ( not spent idly, have been working with lake tangs). Anyway, I am going to re-salt my feet with a 20g. nano reef, low tech, low-moderate lighting. The plan is for a mostly shroom/ softie tank. I have my heart set on a sun coral, so will build the reef with an easy to-get-to cave for easy access to feed. I am in the equipment gathering stage now. I am looking at pc vs. T5 lighting, both fixtures have an even mix of daylight & actinic. I have plenty of experience with pc's and none with T5. I have doubts about pc being strong enough for corals, although I am seeing some awesome tanks on this site with such lighting. Any thoughts or experiences / opinions are welcomed and much appreciated.
Thanks in advance.

crvz
08/30/2008, 09:14 PM
the beauty of the T5 bulbs is that they're small in diameter, allowing the use of individual reflectors. if you get a fixture or retrofit T5 setup with the reflectors, you can keep anything you want. comparing T5 to PC, I'd do T5 every time (and actually do use it on my 150 gallon setup).

mike tv
08/30/2008, 09:20 PM
if hes talking about a 20gal though it should be lit well, provided the PC's are 65w
shouldnt it?

WhiteLightsaber
08/30/2008, 09:27 PM
65w PC's would be good for lighting, but T5's would only take about 29w and give off the same light, provided they were separately reflected.

brighteye
08/30/2008, 09:31 PM
Thanks for your input crvz, How hot are these lights? What I am looking at is a current outer orbit 24" w/ 2 daylight and 2 actinic w/led moonlight and cooling fans. I worry about cooking a 20g. as I don't intend to use a chiller on this tank ( my central air is set at 78 degrees).
Again, Thanks

abulgin
08/30/2008, 09:51 PM
I run a 4x24W T5 setup on my 30g and a simple fan blowing across the top takes care of any heat. The other good thing about T5s is that they maintain their spectral integrity for 12 months, versus 6 months for PCs.

brighteye
08/30/2008, 09:57 PM
Yes, this is a standard 20g. all glass tank miketv. I have 2x 65w pc's on fw planted tanks, and while pretty & effective, they don't dazzle me, I want to be dazzled , but I want to stop short of mh for this tank . so, whitelightsaber, T5's will give the same intensity with less wattage? I appreciate all this input and I don't want to be a pain, but I want to be sure that my first light purchase is the right one. And I really do want to be dazzled, at least a little bit, lol.
Thanks guys

abulgin
08/31/2008, 05:08 AM
T5s will give you the same intensity as MHs only if you're using the same wattage, and then using individual reflectors. A watt is a watt is a watt. In fact T5s won't give you more intensity than CFs, unless you employ individual reflectors. What T5s will do is spread the heat generated by that watt over a longer surface area.

You definitely do not need MHs on this tank. In fact, I don't thin you even need individual reflectors. I keep duncans and shrooms in my 30. You can be dazzled with T5s by choosing the right bulbs.

NaClH20reeffish
08/31/2008, 06:50 AM
<a href=showthread.php?s=&postid=13262540#post13262540 target=_blank>Originally posted</a> by abulgin
What T5s will do is spread the heat generated by that watt over a longer surface area.

Also since T5 bulbs are smaller you can pack more over thesame tank.

But I like that MH shimmer. You don't get that with fluoresents.

crvz
08/31/2008, 07:02 AM
you shouldnt have much of a heat issue with a 4 bulbs setup on the 20 gallon. nothing a small fan can't take care of.

mike tv
08/31/2008, 07:11 AM
try using 5050s in the PC's to get some acitinic or purple light in there
quite dazzling

also, while a watt is a watt is a watt, metal halide is a HID(high intensity discharge) type lamp, and the higher intensity of the light waves coming from the bulb translate into deeper penetration into the water (or so i would imagine, i have very little experience with reef lighting and am sure that refraction plays a great deal in the calculation of such things, but i used to be quite active in the science of lighting from when i was a bit younger, occupying my time with more ill advised horticultural pursuits)

a plant under a flourescent light would nearly die toward the bottom while the top part close to the bulb thrived. Whereas an MH or HPS (both HIDs) would risk burning the top of the plant while having a much more equalized range of lighting down toward the base of the plant, with much less light dissipation across the vertical distance.

(easy there cops, you missed the boat, i was young and dumb and no longer break the law, aside from speeding now and again when im late)


i strongly suggest reading waterkeepers lighting faq, he explains the basic differences between the types of bulbs, and actually is how i stumbled onto this site which interested me in reefing which took away too much money to continue my illegal pursuits. so in a way, reefcentral is my antidrug. haha

in how this applies to our current situation, if you are dead set on using the flouros (and theres no reason you shouldnt be with that much water) then t5s will only offer the benefit of being able to more closely arrange more bulbs of lower wattage. ie buying more lights. if you've already got PC fixtures lying around, personally, i'd use them rather than forking out for the t5s. i've seen an MH used on a 10g nano before with stunning coral growth, so cooling is possible, and a large number of methods from my former passtime could likely aid in that (remoting the ballast, for example, i have not seen done here, which amazes me)

abulgin
08/31/2008, 07:16 AM
<a href=showthread.php?s=&postid=13262845#post13262845 target=_blank>Originally posted</a> by mike tv

also, while a watt is a watt is a watt, metal halide is a HID(high intensity discharge) type lamp, and the higher intensity of the light waves coming from the bulb translate into deeper penetration into the water (or so i would imagine, i have very little experience with reef lighting and am sure that refraction plays a great deal in the calculation of such things, but i used to be quite active in the science of lighting from when i was a bit younger, occupying my time with more ill advised horticultural pursuits)


I agree, but in a 20 gallon tank, a MH overkill. You can keep anything you want in a 20 gallon with T5s.

mike tv
08/31/2008, 07:54 AM
oh absolutely. i meant to quote and credit yours and crvz earlier posts actually, but forgot. it definitely would be overkill. This definitely falls into both the 'many ways to skin a cat' category as well as the 'more is better but how much is too much?' one.
its a matter of opinion on what looks good really. with flouros heat will never be an issue, said plants were known to grow around and touch the tubes while running, and they were incredibly sensitive to heat.

either the t5s or the PCs are definitely your best bet. without a lot of experience with the heat and noise generated by a lot of MHs out there, i wouldnt advise using them.

also, no comments on remoting the ballast? is that common practice in this field? its a fantastic way to move about 3/4 of the heat generated by a MH well away from the subject being lit

brighteye
08/31/2008, 09:25 PM
Hey guys,
Thanks for all the input. So.. despite saying I wasn't going to, I went with the current sunpod 150W,14K HQI-MH w/12 lunar lights. Just gotta have that "shimmer". And should help the colors "pop" for my dazzle. Thanks for all the opinions & ideas, I appreciate it.