T5 lighting question

[vessxpress1]

I didn't find the answer in the existing thread so I decided to post my own. Is 156 watts of T5 light better than 192 watts of PC light? ( 4 39s vs 2 96 PCs) I'm not familiar with it at all but the T5s seem to be getting great reviews. Now I wish I would have waited. Would it make a big difference if I switched? I'm really not a light expert.

[NeilPearson]

I think for SPS the T5 would be better. For anything else, you are fine with the PC

[reefwick]

Waterkeeper has a great thread about lighting. All the ins and outs. Do a search for it but I think its somewhere in the "new to the hobby" forum. If I remember correctly I think T5's are just sizes of the bulbs. I think people are liking them so much now because they can cram more of them in a hood. Check it out for yourself though. If I can get the thread for you I'll post it back here.

[reefwick]

Here you go. The jist of it anyway. Still do the search and read the whole thing. It is such a great read and will answer all you questions about lighting.

Let’s get back to talking about the lamps themselves. Sometimes you smart@ss newbies vex my mind by asking a worthwhile question. Not too long ago someone asked, “ Why are T-5 fluorescents so much brighter and better than T-12?� Normally I can kind of wing it in these threads but, since I really didn’t know the answer, I had to do some, sin of sins, research. Indeed, there were claims of “new technology� surrounding these new “ you can’t do without them� fluorescents but what was the story?

If you have followed this thread you know by now that all fluorescent tubes are similar, that is, they are a phosphor coated tube, an inert gas doped with mercury inside and a filament at each end. Usually the claim made for an improvement in a fluorescent is that they contain a “new improved secret� phosphor. This was true of PC fluorescents when they first came out. As time went by it became apparent that this was not the case and they used the same phosphor blends as most high output fluorescents. With the T-5 it wouldn’t make sense that the phosphor was the “secret� as, if you can coat a 5/8 inch tube with a phosphor, why not an 1.5 inch?

In the past there have been some changes in the fill gas. First there was a reduction in mercury to satisfy the EPA, then a switch from argon to krypton fill gasses to reduce energy consumption. I guess the T-5’s could use radon but I don’t think the Office of Homeland Security would like that idea.

One can change the filaments and here was a lead. The T-5’s produced their highest output a 95º F rather than 77ºF as in T-12’s and T-8’s. This might have some effect but again you could do this with the other size tubes. As it turns out this was done as you can pack more T-5’s into a fixture and the resulting heat inside that fixture is higher.

None of these things would indicate the “secret� to the brilliance of a T-5. Now one thing that came to light when PC tubes first appeared; they did look much brighter than a T-12 when placed beside one. This is true but is also somewhat of a illusion.

Take one of those handy M-33 fragmentation grenades you all carry and place it in a 12-foot diameter sewer pipe and set that baby off. Now do the same with a piece of 10’ and another piece of 7.5’. Now our blessed military has such tight quality control on its weapons that each grenade produces the exact same number of fragments. If you examine the holes the fragments made in the pipes you see a trend, the smaller the pipe the closer the pattern of holes. So be it with a thinner fluorescent tube, more electrons hit the coating per square inch in a thin tube than a wider tube. This makes the light appear brighter but it really does not increase the overall output, just the brightness to the observer.

Clearly there was more to this mystery and as all good mystery writers I leave you hanging to my next installment.

[horkn]

well, even if you dont do sps or clams, the t5ho will save you money on your electric bill, and in replacement interval as well.

156w of t5ho with good reflectors will easily outperform (par wise) 192 w of pc..


hands down at that

[merk1_99]

absolutely T'5 with individual reflectors blows away PC's PC's can only reflect the bottom half of the bulb...I love my Tek's.