Stupid question about lighting...

[lakwriter]

Ok, so I'm shopping for new lights. I'm confused about wattage and the actual light output. In advertising/listing lighting, I understand the whole wattage thing, that I need 3-5 watts per gallon depending on what corals I want to keep. But, is wattage (read: light intensity) equal regardless of the lamps used? I.e. is 36 watts of PC equal to 36 watts of T5? If so, then how is this different from 36 watts of normal output flourescents?

If the reflector ups the intensity by 95%, does that mean you don't need as many watts to achieve your goal intensity?

Or is wattage more a factor of energy consumption?

Basically, my situation is that I want a few softies, a frogspawn, and a bubble coral in my 29g (currently FOWLR) and I only have 36 watts NO lights and I'm looking to upgrade. Specifically retrofit.

 

[jski711]

first of all the "watts per gallon" rule is BS. without getting into specifics the NO lights aren't going to fly. i would either get a pc retro kit or some t-5s. i would go t-5s, more choice on bulbs and better output for corals, usually they come with single lens relectors which is why they are very efficiant. i have a 2x65 watt pc fixture that is fine for softies and some lps in my nano. good luck.

 

[lakwriter]

<a href=showthread.php?s=&postid=9592804#post9592804 target=_blank>Originally posted</a> by jski711
first of all the "watts per gallon" rule is BS.

I know the NO aren't going to work, hence my decision to upgrade... If the 3-5 watts per gallon isn't a good "rule of thumb" then what would be a good way to determine how much light is enough? My tank is 29 gallons, and like I said, I want softies and a few LPS. What would be an ideal wattage? Would it be different if I would choose T5 over PC or vice-versa?

P.S. Metal halide is not an option.

 

[lakwriter]

I'm a girl...forgive my ignorance on the electrical stuff...

 

[JDS]

<a href=showthread.php?s=&postid=9593087#post9593087 target=_blank>Originally posted</a> by lakwriter
I'm a girl...forgive my ignorance on the electrical stuff...

you don't have to be just a girl to be ignorant on electrical stuff. This lighting stuff can get real confusing.

 

[Fish'InMN]

Is the 29g a 30 inch long tank? I suspect it is, which means you'll have a slightly harder time finding a setup that fits over the whole tank.

Generally, PC lighting is less efficient that T5 lighting because of the shape of the bulbs. Then again, what makes T5s so great is the reflector you put behind them, since they are a very thin bulb, so you have to make sure you get individual reflectors.

I can't really recommend an exact item, but if I would start looking at 2 or 4 bulb T5 retros for 24 inch bulbs. You could then stagger the bulbs so that you have a fairly good coverage of the whole tank. I would think a 2 bulb would be sufficient for the frogspawn and some softies, placed accordingly at the top or bottom, but since the bubble coral would probably like to be in a low flow area (on the sand/bottom of tank) also with moderate light, the 4 bulb might be a better option.

Hope this all makes sense!
Marty

 

[five.five-six]

<a href=showthread.php?s=&postid=9593087#post9593087 target=_blank>Originally posted</a> by lakwriter
I'm a girl...forgive my ignorance on the electrical stuff...

ok what the corrals care about are lumens, not watts. lumens is a measurement of light (ie: candle power) generally, if you get a correct amount of lumens, the power consumption will fall between 3-5 watts per gallon..

you are defiantly on the right track. lights vary in efficiency, like cars but instead of MPG you get lumens per watt. and also important is BTU (the amount of heat) per lumen.

metal halides are the best in both respects. even though they get real hot, they are small and give of less btu, they give the best light to heat ratio.. and the best lumen to watt ratio. they should not be ruled out.

 

[lakwriter]

<a href=showthread.php?s=&postid=9593348#post9593348 target=_blank>Originally posted</a> by five.five-six

metal halides are the best in both respects. even though they get real hot, they are small and give of less btu, they give the best light to heat ratio.. and the best lumen to watt ratio. they should not be ruled out.

I have to rule them out because of the room within my existing canopy. too much heat.

I realize having a canopy is not ideal in the first place, but its what I have to work with.

 

[Fish'InMN]

I realize having a canopy is not ideal in the first place, but its what I have to work with.

Actually, I'd prefer a canopy over any other setup, unless you're going for an open top tank and have the hardware to accomplish it. You are completely right about the heat halides generate as well, mine is nearly two feet above the tank and it still warms the water a degree or two, but most lighting will do this to some degree (no pun intended).

 

[REMF]

<a href=showthread.php?s=&postid=9593348#post9593348 target=_blank>Originally posted</a> by five.five-six
metal halides are the best in both respects. even though they get real hot, they are small and give of less btu, they give the best light to heat ratio.. and the best lumen to watt ratio. they should not be ruled out.

I disagree.

T5ho is better than MH when it comes to lumen to watt and lumen to heat also.

Your tank should be L30 x W12 x D18 correct? At 18" deep and 12" wide I would suggest a 4-24W T5 HO retro. Which will be very strong light and you will be able to keep any light loving animal your heart desires.

I would recommend the IC retro from the geek.

 

[lakwriter]

Yep, 30x18x12 is correct. Thanks for the suggestions.

 

[lakwriter]

I see that the IceCap retros have to be wired. Whats involved in the assembly/wiring?

 

[REMF]

It's not hard at all if you are some what handy, however if you don't feel comfortable I would get someone to help you that is.
You can go HERE and see the IC Fluorescent Wiring Diagrams. Plus if you have any questions, all you need to do is ask in the IC forum here on RC and they will hook you up.

 

[Fish'InMN]

Thanks for jumping in REMF; I'm not, or wasn't , familiar with the equipment and what not involved with T5s.

Hopefully you've found some helpful tips here, lakwriter. Keep us updated of what you choose, I'm sure it will be helpful to a lot of folks.

Marty

 

[REMF]

Fish'InMN just for you LOL

 

[Fish'InMN]

I'm not sure I should comment on that, REMF. This is a public, family-oriented site after all.

Brave man though, for the tattoo and the occupation!

 

[REMF]

Aw common man you gotta be a vikes fan, and how about those #2 Gophers this year.

I am from Mankato originally, but now I catch the big fish up here.

 

[five.five-six]

<a href=showthread.php?s=&postid=9594094#post9594094 target=_blank>Originally posted</a> by lakwriter
I see that the IceCap retros have to be wired. Whats involved in the assembly/wiring?

Icecap are very nice! looks lik they now sell an enclosure to do the wireing in. do not save money on endcaps... it is not all that hard to do.. if you are conserned, get some one to help you. the schematic is printed on th balast. I prefer using crimps instead of wirenuts, get a good crimper ~$25 for klein crimpers at home depot and use good 3m crimps. sure a completed retro will probably cost you an extra $70 but it may be worth it. on the orher hand the icecap ballast is very nice, cheep to run, lights run cooler longer and brighter.

 

[hahnmeister]

<a href=showthread.php?s=&postid=9593579#post9593579 target=_blank>Originally posted</a> by REMF
I disagree.

T5ho is better than MH when it comes to lumen to watt and lumen to heat also.

Your tank should be L30 x W12 x D18 correct? At 18" deep and 12" wide I would suggest a 4-24W T5 HO retro. Which will be very strong light and you will be able to keep any light loving animal your heart desires.

I would recommend the IC retro from the geek.

I want to dispell this myth that halides make more heat, and a couple others. Halides have the highest lumen/watt ratio of any bulb... a 3000K can make as much as 105 lumens/watt. The best T5HOs can do (3000K) is about 85-90. Now, what goes in, must come out, so T5s make more heat... its just spread out more. A halide only has a 1" diameter, 4" long area to shed its heat... thats only 12.5 sq. in. of area to pass all of that heat. The same wattage T5 setup will have about 425, or about 34x the area to spread out that heat. The perception is that halides are hotter, and T5s are cooler, but in a closed space, the T5s will heat up more. The pocket of air that they trap between the bulbs/reflectors and the water can heat up the water more than a halide which takes up less space and leaves loads of open area for evaporative cooling. So this idea that halides are 'hotter' as far as the tank is concerned is hogwash. A couple of fans in a canopy will keep any halide in check.

Now, where T5s come in is that as you go bluer, they are able to hold on to more of their output than a halide as it gets bluer. This, combined with the better spread, closer proximity to the water surface, and a few other things... is what makes T5s such a competitive alternative to halides. As far as one being better than the other... I dont think so. They are about the same, and the best tanks I see use them together for the best of both worlds.

 

[five.five-six]

thank you!

what you just illustrated is referred to as: First law of thermodynamics even though the lamp on a mh gets very hot, the volume of heat is less per lumen as a t-5 tube has a much greater surface area per lumen. compounding this is that a greater percentage of the electricity in a mh is converted to light and not to heat. another distinct advantage of the mh is the ripple effect

on first blush this seems counter-intuitive but upon further investigation it is quite logical

also see: Conservation of energy it is the same concept which makes perpetual motion impossible