New tank.. New keeper

[Emg]

Lol on the lighting Slick.... you're right....CF lights do get hot and I would much prefer the T5s myself but I can't fork over the initial cost....and the CFs I have were FREE ! Can't argue that price ! One of these days I'll go for the T5s if someone is upgrading and would like to generously pass on their 36inch T5 fixture to a fellow hobbiest who's down on her luck.....lol I'm still trying to decide if I can afford to pay 50$ for a used fixure just like the one I have but in better shape...with fans that WORK ! It was offered to me by one of the fellas in the local club......it's a great deal but I'm already forking over about 45$ at the next meeting on "other" stuff !

"EH !"


Great info Slick ! Good advice....don't chince out on the skimmer ! You'll never regret purchasing a really good one...but those cheap ones can cause more headaches than they're worth !

[Slick Fork]

Well, you can't beat free! But when you compare the cost of buying new units, I just can't see how anyone could make the argument FOR CF's.

Like I said though, I have a feeling he's going to have to end up going with a 175watt Halide pendant because corner tanks are goofy to get proper light coverage with a strip light.

[joephys]

Its true that T5's are better, but you over exaggerate how 'bad' CF's are.They aren't horribly inefficient, about 10-20% less depending on the bulbs, meaning they run 10-20% hotter. It makes a difference, but CF's aren't as horrible as you make them out to be.

Really when push comes to shove, you get more light per watt with metal halide lighting. They just seem really hot because you have a lot of power in a very small space. If you could cram all of the energy released by any fluorescent bulbs using the same amount of power, they would produce more heat than an MH bulb.

[Slick Fork]

I don't know why CF's get under my skin, they just do. It's not like I've ever lost a family member in a tragic lighting incident...

They are quite a bit less efficient. The key difference is what you can keep under them. Cf's are fine for FW planted tanks or Macro algae, but to use the example of a 192 watt cf fixture (2x96) it's actual comparison when you look at Usable light (PAR) would be closer to a 2x39 watt High output t5 fixture. A 4 bulb T5 like I mentioned will give enough light for SPS corals 18" lower. I can't imagine how many CF lamps you would need to light an SPS coral 18" below the surface.

I guess that's why it bugs me, not so much for people that have had them a while, just when I see them being recommended as a good option BRAND New. If we were talking $300 difference than sure, but for $100 get a fixture that will do the job.

[Slick Fork]

Oh, and yeah I agree. MH's are the most efficient thing we've got now, watt per watt

[joephys]

If you have a reference for that I would like to see it. What you are saying is that there is a 240% difference between CF's and T5's. That seems like way to big of a difference.

[Slick Fork]

I'll try to dig up an actual scientific reference in a bit, no time right now. Do a search on Reef Central for T5 tanks and be prepared to be floored.

Shooting from the hip... I've seen with my own two eyes in person acropora's flourishing 18" under 4 bulb t5 fixtures. I have NOT seen CF's producing anywhere near that amount of light, I wouldn't put an acropora 6" from the surface under a CF light and expect it to thrive. My 2x39watt comparison again is a visual comparison between what's flourishing in a tank with 2x 96 watt CF lighting, like EMG's tank, and what I've seen growing in T5 tanks.

A huge portion of the T5 advantage is the individual reflectors like the Tek unit has. So much of the light generated in a CF is just wasted energy.

Like I said, if you can get one free or at an enormous discount I wouldn't criticize anyone for grabbing a CF fixture but if we're comparing brand new retail prices I think you'd be foolish to choose CF, especially a coralife brand fixture.

[Emg]

No doubt T5s and halides are better for a reef all and all, especially if you have your sites on SPS coral or anemones and clams......also, T5s for one are a lot more efficient than CF and less costly to run. LED lighting is even better when you want effects...there's a fella around here who has a computerized LED lighting system over his tank with all sorts of bells and whistles...fantasic ! But, it costs thousands of dollars...no lie ! He got a deal on it from the company for some reason and didn't pay full price, but still was a hefty piece of change.

CF lights are good enough if your tank isn't that deep and you're going to be sticking to the lower light soft corals. For a little bit more change it makes sense to go with the T5s like Slick says...if you have the extra to spend. They're more efficient, don't run as hot and ...if you change your mind down the road and want to give SPS, clams or anemones a try....you won't have to purchase a whole new light fixture.

I tank on a budget and have to take what I can get when I can get it.....I would have liked a 65g tank, but because of my lighting I went with the shallower 50g. No biggie, and I enjoy it just as much...but CF lighting will definitely limit you to some degree.

[joephys]

Originally Posted by Slick Fork

...
A huge portion of the T5 advantage is the individual reflectors like the Tek unit has. So much of the light generated in a CF is just wasted energy.
...

That is the key difference right there. I have been talking purely about total light generated by the bulbs. In that regard, T5's are only about 10-20% more efficient. If you have good reflectors, then yes, you can get a lot more of the light emitted from from T5's going back into the tank instead of back into the bulb. Most manufactured CF fixtures have horrible reflectors in them, that are almost worthless because they reflect light right back into the bulb. There are T5 fixtures out there with reflectors that are just as bad, with bulbs packed in right next to each other. Again, no room for the reflected light to escape. I would be willing to bet that those fixtures are not much better than CF's.

I'm sorry, I don't mean to be rude or argumentative, but until I can a see side by side comparison of two similar setups, I just can't believe that there is an over 240% difference between T5's and CFs. A CF bulb is basically a T6 bent around on itself, and they work on the same principles. Unfortunately there isn't much data that is easy to find on the efficiency of T5 lighting to compare.

Diodes, if you are using white diodes, they are nice because they give you a nice smooth spectrum with a peak in the blue. This gives you much truer color than you would with any fluorescent or MH bulbs, and no need for actinics.

[joephys]

Well here is the best info I can find right now, its not the best sources, but like I said, its hard to find good ones, and it using lumens, which is a bad way to compare lighting. There are too many variables to make a perfect comparison, but if you look at the 54 watt T5 HO it produces 5000 lumens at its peak. The CF bulb produces about 4600. Thats about a 10% difference.

What T5 lamps are available? | T5 Fluorescent Systems | Lighting Answers | NLPIP

Bulbs (towards the bottom)

As was mentioned by both of us though, I think reflectors and geometry are the biggest factors in how well they light up an aquarium.

[canardman]

So a T5 setup is not much different than a CF. Price wise, they are a bit more. What is the selling point on the T5's?

[joephys]

There is difference, and it can be seen. I Happen to feel that the difference isn't as great as slick fork however.

The biggest selling point for T5's that I can make is that the lights themselves are somewhat more efficient. If the reflectors are done properly, then they will put more of the light into your tank than a CF fixtures due to light being reflected back into the bulb. If you look at a T5, its a single tube, so all of the light goes out away from the bulb. With good reflectors, only a small amout will be reflected back into the bulb. With CF bulbs, you have two tubes right next to eachother, so maybe about an 8th of the light goes directly into the tube next to it. In also increases the surface area for reflected light to restrike the bulb, meaning less reflected light into the tank. All of this bulb restrike reduces the ammount of light entering the aquarium, and is basically just heating up the bulbs, making a hotter envrionment inside the light fixture.

The one issue is if you have a T5 fixture with all of the bulbs right next to eachother, you end up with the same restrike issues that the CF's had.

[canardman]

So, it would be worth the time to engineer an efficient reflective CF unit. I have more time than money, and the setup to make a nice fixture. Saving money for live rock!

[joephys]

You could work on that, but the issue that comes into play is the width the reflectors would need to be. Good reflectors are great, but you can only reflect light if you have the bulbs to produce it. Compact Fluorescent Lighting Kits has some of the best reflectors you will find for CF bulbs.

As far as live rock goes, if you want to save some money there, which it will probably be your biggest cost, you can buy your make base rock, and buy 30-50% of the live rock that you would have otherwise purchased. It will take some time for the base rocks to become fully alive, but its a way to save money.

[Slick Fork]

The reason side by side comparisons using a par meter are hard to find on the web is because it's not even a close comparison.

You will find side by side comparisons of metal halide and t5 fixtures because they are closer. Saying that the reflector advantage is beside the point makes no sense, it's part of the whole picture. A t5 with a crummy reflector compared to a cf with an ok reflector will still be more efficient (I say OK because there is no such thing as a great CF reflector). This is becoming a ridiculous argument. Simply look at what can be kept under each style of light and that will tell you more about effectiveness and efficiency per watt of energy consumed than a par meter ever will. I can understand a debate of MH over T5's but this is like comparing an incandescent bulb to a candle. If you really have doubts, post on reef central where there are TONS of people ranging from scientists to electricians and ask them their opinion. I'm not even going to touch your LED comment.

Canardman; I've said my bit, I think T5's are the way to go and you can DIY a t5 fixture just as easily and cheaply as you can a CF fixture. Besides being a more efficient light source, you also have a MUCH MUCH bigger selection in terms of colour spectrum in the bulbs to choose from. Look at the whole picture, if you can't make up your mind with our advice here then go to Reef central and ask what they think there. At the very least you will get more people arguing then me and Joe.

[joephys]

Your right, this is a pointless argument since you are now putting words in my mouth. I never said the reflector was besides the point, in fact I said that reflectors are the biggest issue. I have at least posted some links to support what I have been saying.

I was wrong about the diodes, The newer high output ones do produce about the same amount of light per watt as a CF, but they are focused a lot better if you get good ones.