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View Full Version : Led VS T5s Vs MH!@!@3#


huskysglare1
11/16/2008, 07:51 PM
Which one offers the best growth? Please give Details. l am interested in knowing the difference in performance not the price. Please share your opinion.

Aquabucket
11/16/2008, 08:11 PM
First off the lighting you choose is going to depend on 2 major things. The livestock you want to keep and the depth of the tank. MH penetrates the deepest of the 3. T5s are pretty good for tanks under 20" or so. LEDs are the light of the future and will probably be the lighting of choice within 5 years or so. MH will likely still be needed on deep tanks with high light demanding livestock.

Fish_wiz2
11/16/2008, 08:31 PM
<a href=showthread.php?s=&postid=13759415#post13759415 target=_blank>Originally posted</a> by Aquabucket
First off the lighting you choose is going to depend on 2 major things. The livestock you want to keep and the depth of the tank. MH penetrates the deepest of the 3. T5s are pretty good for tanks under 20" or so. LEDs are the light of the future and will probably be the lighting of choice within 5 years or so. MH will likely still be needed on deep tanks with high light demanding livestock.

saved my keyboard! but anyway i like MH because it is relatively cheap and like aquabucket penetrates deep

nikon187
11/16/2008, 08:33 PM
growth would depend on alot of things, depth of tank, wattage of bulb, number of bulbs, colour temp of bulb ect. Led's are comming along but not quite there yet for me to spend the money

IslandCrow
11/16/2008, 08:59 PM
Good luck getting any useful information. I don't think there are two many people who have used all three on tanks even remotely similar.

edwing206
11/16/2008, 10:16 PM
MH gives nice shimmer lines. Ooooh, aaaah. :lol:

huskysglare1
11/17/2008, 02:28 PM
t5 and MH are pretty even. Which one has more benefits?

Nolimdien
11/17/2008, 03:33 PM
It depends on what corals you are trying to grow. I've seen amazing tanks with both MH and T5.

Your question is too vague.

Michael
11/17/2008, 03:35 PM
<a href=showthread.php?s=&postid=13759779#post13759779 target=_blank>Originally posted</a> by IslandCrow
Good luck getting any useful information. I don't think there are two many people who have used all three on tanks even remotely similar.

yep i agree, i like t5s, and think high powered LEDs are the future, but as island crow has rightly stated theres not going to be many guys who have experience of all 3, there completely different and its a difficult 1 to answer:)

miniwhinny
11/17/2008, 03:54 PM
It comes down to something simple for me. MH and T5's work great but I just can't give up the "glitter" that my single point MH gives me.

crvz
11/17/2008, 05:07 PM
Yep, as is being implied, there are WAY too many variables to say one is better than the other. They can all be employed with equal success depending on tank setup, photoperiods, tank dimensions, among probably ten other things.

xJimCx
11/17/2008, 08:28 PM
The MH shimmer does it for me...

noboddi
11/17/2008, 08:42 PM
T5 hands down. You can get them to penetrate to 30" if you have the right reflector.

By getting the right bulb mix, you can bring out the colors in the tank and display everything at it's best. Corals also color up better under them IME.

Shimmer won't be a factor for long. Aquactinics is prototyping T5 fixtures that incorporate LEDs, not for lighting but to add the shimmer.

Fauna Marin is coming out with dimmable T5 pendants in January.

Just a lot of flexibility. Read Grim Reefers website and posts and learn all you want about lighting

MMOORE0324
11/18/2008, 12:57 AM
T5s all the way for me. I have T5s and MH on two different tanks right now. I have 2x25014k MH on my 150 mixed reef. And I have 12 t5s on my 75 SPS tank. I have much faster growth AND amazing color with my t5s on the SPS tank. The nice thing is that you can have your tank look just like you want by mixing different color bulbs. I have 12 bulbs and I only have 3 11k (White) and a mix of 9 actinic and blue bulbs. Its great. I am thinking about selling my MHs and going with t5s on my 150 too. Not to mention the money savings and very little heat. I think that LEDs might be the way of the future but just not there yet. I also think that with time that T5s and LEDs will take MHs and VHOs out of the hobby, IMO. Check out October 2007 TOTM. Paul has a 500g SPS dominated tank lit with only t5s.. 28 of them I think.

eros
11/18/2008, 03:05 AM
How do you fit 12 T5's over a 75 gallon tank? Do you have any pics of your lighting setup?

huskysglare1
11/19/2008, 11:14 PM
a lot of people uses MH. Does that produce better results?

hahnmeister
11/20/2008, 12:20 AM
<a href=showthread.php?s=&postid=13759415#post13759415 target=_blank>Originally posted</a> by Aquabucket
First off the lighting you choose is going to depend on 2 major things. The livestock you want to keep and the depth of the tank. MH penetrates the deepest of the 3. T5s are pretty good for tanks under 20" or so. LEDs are the light of the future and will probably be the lighting of choice within 5 years or so. MH will likely still be needed on deep tanks with high light demanding livestock.

A photon is a photon... doesnt matter if its halide or T5. What matters with regards to 'penetration' or rather, how much a light field will travel w/o losing intensity is the dispersion, or area of the source. At that... watt per watt, T5's have the advantage because they are much less of a point source than halides. That 'shimmer' that halides produce is actually an indication of how it is an inferior source of light when it comes to 'penetration'. Less shimmer = more penetration (there are exceptions, but for these two, its correct). Even with reflectors like lumenarcs, the overall effect is still very much a point source (just look at the grid testing Sanjay has done)... since even though the reflector is spreading out the light that comes out of the top half of the bulb across a larger area, its still less than half the output of the bulb (which is usually about a 4" long tube of light), and the light that the reflector works with diminishes because of the reflector's material and the distance it has to travel from the bulb to the reflector.

Now, halides have an advantage as far as power density... you can pack more wattage into a smaller area... so in that respect you can put more wattage into a smaller area above the tank... but if your tank has enough room to run similar wattages of Halides OR T5's, the T5's, the T5's will 'penetrate' better.

Now I dont know about 12 T5's over a 75g. You can do a geometric proof for the 'minimum reflector width' using a 100% cirvilinear reflector, and it comes out to just over 2"... about 2.15". Now, this is just a 'perfect' reflector in the sense that all of the light from the back side (about 200 degrees) of the reflector is being reflected out the front w/ none being reflected back at the bulb. When you start going under this width, or using a reflector with flat facets (not curvilinear), you end up with losses in output. And then, to direct the light downwards even better... the 'gullwing' design has the outer 30% of its 'wingtips' bent upwards/outwards to angle the light that hits there down rather than to the sides. Now we are looking at something more than 2.15"... more like 2.5" to 3". This isnt a 'better' reflector, but just guides the light more to where most of us want it... down. Anything less than this 2.15" width is 'cutting corners' (flat facets pushes this minimum up even more... the more curvilinear, the narrower the reflector can be). Maybe just the center backside (about 20%) of the bulb is neglected a little to spend more attention on the frontside while keeping the reflector at a decent width.

But 12 T5's over a 75g? I bet an 8 bulb system with proper reflectors will make just as much light since 12 bulbs means a reflector width of 1.5"... which means a good 30% or more of the bulbs output is being wasted somehow (reflected back at the bulb or at another bulb most likely).

Slakker
11/20/2008, 12:35 AM
+1 to hahnmeister.

I prefer Halides, myself...I like the color of my 14k bulbs.

JustinReef
11/20/2008, 01:12 AM
I switched to T5 from halide last year but after 6 months went right back. I prefer halides. I spent a fortune on expensive T5's but the lack of shimmer and just the overall look didn't do it from me.

I didn't find them all the cooler either. Certainly not as hot as halides but not that cool I didn't think.

hahnmeister
11/20/2008, 01:24 AM
"watt for watt", T5's and Halides generate similar amounts of heat. The perception that T5's make less heat is not correct. It is due to the lower temperature at any given point compared to halide (since a T5 bulb has about 40x the surface area per watt to shed that heat). What often is true though is that T5 systems usually include some form of active cooling (fans) which also ends up helping keep air over the water surface cooler as well. Many halide systems dont have fans so they dont cool as much... but those that do see similar benefits. Some halide pendants even have air ducting ports right on the units themselves so the hot air that the bulbs conduct/convect can be migrated right out of the system all together.

buerk212
11/20/2008, 01:42 AM
I have two 150W MH 14k, two 54W actinic T5HO, and 14 blue LED's on my 75 gal. All together it gives it a really nice bluish shimmer. More importantly I just have xenias, polyps, and a frogspawn coral that I've had for a few months now and they are doing really well. I had PC lighting before this set up and it doesn't compare to the MH’s...

tonyf
11/20/2008, 01:49 AM
+ more for Hahn :)

I read somewhere Hahn, that the light intensity off T5's, like NO tubes, wanes towards the ends of the tube such that the PAR readings along the length of a T5 tube at a prescribed constant depth are lower at the ends than in the middle. Is this correct?

IMO, T5 and MH have their place and neither has an overall superior reason to use one over another. And, LED's have come along way over the past few years and still have a long way to go to become the superior product.

Tone :)

JustinReef
11/20/2008, 01:59 AM
I agree that one is not more superior. For me its just personal choice to go with halides. Actually I still use T5's for actincs though.

onano
11/20/2008, 06:10 AM
I have both MH and T-5's on my 75. I really started to see the growth when I added the T-5 actinics vs. the old PC actinics. I like my current combo but could see all T-5's working nicely if I ever go to a larger tank.