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View Full Version : T-5 vs. PC question


Reefer07
06/24/2008, 10:03 PM
I know this has probably been brought up plenty of times but I am looking for some of you to convince me that T-5 is better than PC lighting. Right now I run PC and just from word of the mouth and reading on here I am aware that T-5 is generally better liked.
My only concern is when I upgrade to T-5 I am actually going to have less wattage.
Right now I run a 24" dual PC- 130 watts total.
I have a 29 gallon tank and I am looking at a 30" tek light setup with 100 watts total.
When I change to the T-5 I am obviously going to be running less wattage so does that mean my corals are going to be looking for more light since they were used to 130 watt or is the T-5 going to be better because it is a better quality?

Any reading or further information is greatly appreciated.

Thanks,
Zac

Phong33
06/24/2008, 10:37 PM
This should speak for itself. The top pic has PC's as actinics (55w each) and the bottom pic has T5 as actinic (24w each). You tell me which one is brighter.
Yes T5's use less energy which just means less on your electric bill for more light (particularly PAR), and it runs cooler.

http://i8.photobucket.com/albums/a8/Phong33/DSC02271.jpg
http://i8.photobucket.com/albums/a8/Phong33/29g/29g303.jpg

eddnyster
06/24/2008, 10:41 PM
Don't focus on watts
what you should look into is PAR, which is
the light that is actually being exerted onto your corals/animals
Watts simply states the consumption being used by the light

This subject is really really involved and a little complicated but once you get over the whole "Watt is a Watt" issue it'll be easy to understand.

In simplest terms think of as...the energy saving bulbs at Lowes or Home Depot. Energy saving bulbs use less watts but emit more light that traditional old bulbs.

Reefer07
06/25/2008, 05:13 AM
That's all you need to tell me. The picture helped a lot too.
Also, is PAR measured and stated on the lightbulb or do you need some kind of instrument to measure this?
Thanks guys!

RRaider
06/25/2008, 06:24 AM
Reefer07, I just installed t5's (retro kit) on my 29 and I guarantee you won't be sorry. Just make sure the TEK fixture has individual reflectors.

mojo~
06/25/2008, 08:58 AM
T5 with indiv reflectors are far better than the PC's The pics show it all. I have used both and there is no comparison.

sly fox
06/25/2008, 09:31 AM
agree t5s

x2uranium
06/25/2008, 10:46 AM
convince me that T-5 is better than PC lighting:lol: :lol: :lol: :lol: :lol: :lol:

AwkwardParrot
06/26/2008, 07:15 PM
be bran prefered, i want to know who makes the best. I had a 48" current USA orbit 6x54w, loved it on a 75....looking at a 29g, whats a good light for LPS, SPS, and some shroomes?

DarG
06/26/2008, 08:29 PM
Reefer07 ... its the reflectors for T5. They are the single largest reason why T5 is the most efficient and most effective flourescent lighting source for the tank.

The small diameter of the bulb allows the design of individual reflectors for each bulb that reflect nearly all of the light from the T5 back into the tank.
The TEK fixture has these individual reflectors.

It isnt even close when comparing 100 watts of T5 with good reflectors compared to 130 watts of PC.

The only light from T5 not making back to the tank is a little bit on the very top that reflects back into the bulb itself.

Reflectors for PC's cannot be designed to be nearly as efficient or as effective because of the profile/shape of the bulb and the size that the reflector would have to be because of the shape/size/width of the bulbs. Even a reflector large enough could not be as effective because the geometry of the bulbs.

VHO would require relatively huge reflectors compared to T5 and this would make it impossible to use enough VHO over a tank to be as effective as T5.

The new internally reflected PCs still cannot compete because the reflectors inside the bulb cannot reflect nearly as much of the bulbs light nor can it do it as effectively because they cannot be optimized like extrernal reflectors which actually envelop the entire bulb when designed as effectively as possible.

Again, its not even close.

englishreefer
07/01/2008, 08:17 AM
Them pics don't really show much. Take a look at the middle two day light tubes in both pics. Pic 2 is brighter than pic one when should be the same.

DarG
07/01/2008, 09:04 AM
<a href=showthread.php?s=&postid=12857052#post12857052 target=_blank>Originally posted</a> by englishreefer
Them pics don't really show much. Take a look at the middle two day light tubes in both pics. Pic 2 is brighter than pic one when should be the same.

Why should they be the same? Pic 2 shows T5's, Pic 1 shows PC's.

The issue I have with the pictures is that the center PC tubes in pic one look like 420nm actinics and the center two T5's in pic 2 look like 10K daylights.

But it's irrelevant. The difference is night and day comparing the pics of the blue tubes and this entire topic is beat to death years ago. The wattage differences and par per watt comparisons are NOT the key to the discussion. The reflector is the key to the discussion and so much of it is common sense that this issue isnt even debateable. Its like comparing how much light two metal halide bulbs direct into the tank. The halide bulbs are the same, one is enveloped in a top quality reflector and the other has no reflector at all or a flat reflector sheet above the bulb only. That is basically the equivalent scenario.

It seems that only those who dont have much common sense still argue this after the details are presented. No hobbyist would have a reason to lie about this. They arent vested in the T5 market. It would be great if PC was as efficient and effective because it is so much cheaper now for a PC set-up. If one cannot get past the watt's issue then any further explanation is a waste of time.

It's the reflector.

AwkwardParrot
07/01/2008, 09:34 AM
T5s seem to have a sharp light all the way across tho.

DarG
07/01/2008, 10:01 AM
<a href=showthread.php?s=&postid=12857571#post12857571 target=_blank>Originally posted</a> by AwkwardParrot
T5s seem to have a sharp light all the way across tho.

Not sure what you mean exactly. The reflected light is very bright. The light radiated directly by the bulb is bright but the light reflected by the reflector is also impressively bright. If thats what you are talking about ... ??? But its not a point source light and the light is not concentrated only in a small area under the bulb so that it is bright only in a small area in the tank.

It's just like any other reflector in that the light spread gets wider as the distance from the reflector increases. T5's are used in an array ... 4 bulbs, 6, 8 ... whatever. The more bulbs the wider the spread, obviously, and also the higher the overall par in the tank.
The light isnt just bright right under the bulbs. The relfectors have alot of reseach and design that went into them so that they maximize light produced by the bulb in terms of directing nearly all of it down into the tank and they optimize the spread of the light as well.
The good reflectors differ slightly ... for example The Icecap SLR's have a little narrower spread than the TEK's, especially the TEK 2's which have a little wider spread. So the Icecaps would concentrate the par into a slightly narrower area which is generally considered better by most for our reef applications. This also gives the Icecap SLRs a little more par at depth I believe.

The point is that there is real engineering and design that goes into the reflectors. They took full advantage of the benefits of T5 in terms of shape and size to design higly effective reflectors that simply cannot be designed for PC (because of shape/style/size).

Im not a T5 expert. I dont even use them for main lighting. I use halides with 2 T5s as color supplements. I have no vested interest in T5's over PC's. They are simply more effective and efficient because of the reflectors in large part. But they also last longer than PC. They cost less to operate because you dont need as much wattage to get as much light. They also generate less heat than PC because you need less wattage. Those are just some of the facts.

I use them as supplemental lighting because they offer the most light in the least space for flourescent supplements. They also have more bulb colors available than other flourescents.

Talk to Grim Reefer here on the forum as he is one of the T5 experts. He can offer more technical info if you need it.