Radion vs. MH

[chucelli]

If one is to argue for LEDs (since I see this thread going beyond the Radion units and venturing into general LED), arguing based on perceived economic advantage is flawed even if you build your own. You have to factor in the time required to research, build, and costs of tools and materials required. Commercial systems aside, (since I have no personal experience with them) LED technology does have certain distinct advantages over other forms of lighting.

 

-Heat radiation (lack of):

This advantage is not about whether or not you can save on electricity because you are no longer putting heat into your tank or house via lighting. You don't want to put heat into your tank via lighting because this results in a daily spike when the lights are on. The temperature then starts to drop when the lights are off. For the record, I don't think it's that important that the water temperature remains static on a day to day basis. However, an overall consistent average temperature is important and LEDs make it much easier to maintain average temperature year-round. Water heaters, because of their direct contact with the water, results in faster and more consistent heat exchange, which ultimately results in better temperature management (vs heat exchange via lighting). So in short, it is much easier to manage water temperatures with just a heater, rather than a heater plus lighting (plus chiller in some cases).

 

-Hardware longevity:

In addition to the already mentioned bulb replacement costs (which I feel is secondary), eliminating bulb replacements also contributes to environmental stability. New MH bulbs lose much of their maximum intensity within the first few days, then output slowly drops over a longer period of time. This is especially noticeable when there is a constant relative light source (such as LED) for comparison. You can imagine what those first few days of a new MH bulb feels like on your corals.

As for LED failures, I don't know anyone with a DIY unit that has had any LED failures not related to misuse or accident. The commercial units IMO are more prone to failure due to inherent weaknesses of circuit-board use in these types of applications.

 

Finally, I would avoid making PAR comparisons based on wattages, since there are multiple MH bulb choices within any given wattage, all with greatly varied PAR output. Add all the different optics, colors available for LEDs, and the fact that most commonly used PAR meters do not give correct weight to spectra found in abundance in blue LEDs, there is no accurate way to make on-the-fly comparisons.

 

-Robert

[hypertech]

You make good points.

 

About temperature, I really don't think its that important to have such fine control over temperature. I've had tanks with up to a 6 or 7 degree daily swing (a 150W halide built into the closed hood of a BC29) that flourished. Not too long ago, there was an article on reefbuilders about a liquid cooled LED heatsink and a bunch of comments directed to how great it would be if you could pump tank water through it so that they wouldn't need to run their heaters as much. I thought it was pretty funny. Most people refer to limiting heat into the tank as a big benefit of the LED and here were a bunch of LED users trying tot get the heat into the tank.

 

About longevity, LEDs lose their intensity too albiet over a longer period of time. The difference is that I can throw a new bulb in a halide fixture and its as good as new. Its not so easy and much more expensive to replace LED emitters. Regarding stability due to new bulb burn in - well, there are cloudy days and sunny days in the ocean. I suspect it is like having a sunny day.

[nbgen12]

Sent from my MB860 using Tapatalk 2

[chucelli]

 

About longevity, LEDs lose their intensity too albiet over a longer period of time. The difference is that I can throw a new bulb in a halide fixture and its as good as new. Its not so easy and much more expensive to replace LED emitters.

 

Much longer period of time. 25% loss over 10 years is null relative to MH. This 25% loss can easily be made up with higher drive currents assuming the LEDs were not driven at 100% of max spec'd current. With the newest emitters available, there is no need to drive them at their maximum rated current.

 

Regarding stability due to new bulb burn in - well, there are cloudy days and sunny days in the ocean. I suspect it is like having a sunny day.

If sunny days only happen once every six months, I would say your comparison would be accurate.

 

-Robert

Edited June 1, 2012 by chucelli

[hypertech]

LEDs lose their intensity much quicker if the junction temperature gets too high. All these "cold" heat sinks that people and manufacturers like to flaunt as evidence that their fixtures are so great actually has me thinking that they aren't being cooled well and the junction temperatures are actually too high making longevity suffer.

 

A sunny day is a sunny day whether its every 6 months or once a week. I think the corals can handle it just fine.

[chucelli]

LEDs lose their intensity much quicker if the junction temperature gets too high. All these "cold" heat sinks that people and manufacturers like to flaunt as evidence that their fixtures are so great actually has me thinking that they aren't being cooled well and the junction temperatures are actually too high making longevity suffer.

 

You are absolutely right. Keeping these high wattage LEDs cool and within ideal operating temperature has been one of the major challenges in implementation. Many manufactures skimp in this area to cut costs since it is very expensive to implement and is an area that consumers can't easily see without dissection and proper testing. However, this does not invalidate the facts of LED's superior lumen maintenance properties.

 

A sunny day is a sunny day whether its every 6 months or once a week. I think the corals can handle it just fine.

 

"handle" is a relative term. I think they will survive just fine, but growth will no doubt be stunted, at least this is what I've noticed. Adaptations that have come about to work with 6 months of continuous cloudy will not work ideally on a sudden "sunny" streak. They will need to re-adapt and this takes a painfully long time.

 

-Robert

Edited June 1, 2012 by chucelli

[hypertech]

You are absolutely right. Keeping these high wattage LEDs cool and within ideal operating temperature has been one of the major challenges in implementation. Many manufactures skimp in this area to cut costs since it is very expensive to implement and is an area that consumers can't easily see without dissection and proper testing. However, this does not invalidate the facts of LED's superior lumen maintenance properties.

 

 

It does in fact invalidate their lumen matinenance properties because they output can drop to 70% or even 50% or less over a relatively short period of time. I had a friend jump on the early adopter train and go to an AI fixture for a couple years. Half the LEDs burned out over that period. I'd say a reduction to zero is a siginificant lumen maintenance problem.

 

 

"handle" is a relative term. I think they will survive just fine, but growth will no doubt be stunted, at least this is what I've noticed. Adaptations that have come about to work with 6 months of continuous cloudy will not work ideally on a sudden "sunny" streak. They will need to re-adapt and this takes a painfully long time.

 

-Robert

 

If you are really that worried about it, point them at the wall for the first day or so when you add a new bulb and let them suffer through a cloudy streak. Its just not a big deal.

Edited June 1, 2012 by hypertech

[basser9]

The radion lacks the correct optics for large tanks but they have some you can pk up now.

Its a nice light but with the price of rebel and cree around 3 dollars a piece you will see way better

led fixtures within the next 2 years that will pretty much start the decline of mh usage.

Ihave no dought that 10 years from now its all leds over ever tank.

All of the chinese lights are starting to use rebel or cree and it will drive the price down.

Diy led are so much cheaper then a mh setup that its a no brainer but the radiums are to high.

 

I have run mh for 15 years and the biggest savings comes from the ramping up and down of leds

running lights full blast for 10 hours eats electric like crazy and the summer heat was bad.

 

People dont relize how much better a cree xml vs a cree xre is in terms of heat.....

Even a xte run at 1000ma is cool vs a old xre that people used 2 years ago.

These newer rebels and crees are so cool running and powerful that mh seem like

tube tvs.

 

The rebel es royal blue is out and steves led has them for 3 bucks.

At 1000ma they blow the cree xte rb out of the water and run cooler

these are the leds that are so exciting and when the radium has xml and rebel es leds

in them then i would buy them for a deep tank.

Edited June 1, 2012 by basser9

[zygote2k]

MY example is this-

I have one of Chucellis fixtures over my 36" cube tank. It produces 108w of light from 18 blue and 18 white LED's running at 100% for 8 hours and half of them for 4 hours. Let's round it and say 10 hours total.

If I were using conventional lighting, I would be using a 400w mh pendant with 2) T5's for the same time period. This is roughly 4 times the electricity usage alone.

The mh pendant would also raise my indoor temperature by a few degrees, causing my house a/c to run longer. If you want to use the argument that with LED's, you now have to run your submersible heater longer, than we can cancel out the running of the central a/c to deal with the excess heat.

We're still at 4x electricty use with conventional. I tell people to expect 5 years out of hi- quality LED fixtures and 2-3 years on mass produced units from China and elsewhere.

In those 5 years, I would replace 5) mh bulbs @ $50ea and 10) T5 bulbs @20ea. That's $450 in bulbs.

The LED fixture that I have was roughly $600 and a brand new, nice quality 400mh/t5 pendant is roughly the same price.

As far as whether or not pieces or components break on either fixture, those are unknowns.

With my comparison it still makes more sense to buy an LED fixture if you need a light source.

You also have to remember that LED manufacturers are recommending that you buy more fixtures than you might actually need because they won't get as much repeat business like users of conventional light systems.

Many people also put way too much LED's over their tanks because of the manufacturer recommendations. Everybody doesn't need perceived SPS capable lighting. If you are growing everything else but a full blown SPS tank, you can get by with half of the recommended amounts of light.

Radions are still drastically expensive compared to other makes on the market. You don't really need full dimming and weather simulation to grow corals. We;ve been doing just fine without these features for the past 25 years.

Edited June 1, 2012 by zygote2k

[basser9]

A underrated thing about the radion is the ability to adjust the red spectrum.

The red slime slash hair algae battles are usally related to the shift in mh

as they age.

As great as a bulb as the radium is it shifts toward the red spectrum as it ages.

Being able to ramp down the leds when adding new corals and ramping them up

as they age to keep the par the same over the years.....alot of things the leds can do

are nice.

The radion does alot of things right....except the price

[hypertech]

MY example is this-

I have one of Chucellis fixtures over my 36" cube tank. It produces 108w of light from 18 blue and 18 white LED's running at 100% for 8 hours and half of them for 4 hours. Let's round it and say 10 hours total.

If I were using conventional lighting, I would be using a 400w mh pendant with 2) T5's for the same time period. This is roughly 4 times the electricity usage alone.

The mh pendant would also raise my indoor temperature by a few degrees, causing my house a/c to run longer. If you want to use the argument that with LED's, you now have to run your submersible heater longer, than we can cancel out the running of the central a/c to deal with the excess heat.

We're still at 4x electricty use with conventional. I tell people to expect 5 years out of hi- quality LED fixtures and 2-3 years on mass produced units from China and elsewhere.

In those 5 years, I would replace 5) mh bulbs @ $50ea and 10) T5 bulbs @20ea. That's $450 in bulbs.

The LED fixture that I have was roughly $600 and a brand new, nice quality 400mh/t5 pendant is roughly the same price.

As far as whether or not pieces or components break on either fixture, those are unknowns.

With my comparison it still makes more sense to buy an LED fixture if you need a light source.

You also have to remember that LED manufacturers are recommending that you buy more fixtures than you might actually need because they won't get as much repeat business like users of conventional light systems.

Many people also put way too much LED's over their tanks because of the manufacturer recommendations. Everybody doesn't need perceived SPS capable lighting. If you are growing everything else but a full blown SPS tank, you can get by with half of the recommended amounts of light.

Radions are still drastically expensive compared to other makes on the market. You don't really need full dimming and weather simulation to grow corals. We;ve been doing just fine without these features for the past 25 years.

 

There just isn't any logic to this. You are advocating an LED setup that has a pretty small number of LEDs and arguing that most people are suggesting too many LEDs for full blown SPS tanks and everyone doesn't need it. Then, you compare to a 400W plus 2 T5s lighting, what I certainly would consider lighting for a full blown SPS tank. Unless you can produce PAR numbers that 36 LEDs are equivalent to 400W plus 2T5s, this is a wholly skewed apples to oranges comparison.

[basser9]

Heres some par numbers that help.....

 

The standard par for a 400 watt radium at 12 inches under the water is 320 with a nice reflector.

2 ai are 48 3 watt crees with 40 optics inside and 70 out.

I CAN BUILD a diy led array with 36 leds that will easily out perform a 400 watt radium in par..spread....color and eletric use.

If i use xml and rebel es rb in 2 pods like a radium style i can do it with 30 or less.

 

The led fixtures of the future will make mh look like 8 track players in 5 years.

 

[zygote2k]

There just isn't any logic to this. You are advocating an LED setup that has a pretty small number of LEDs and arguing that most people are suggesting too many LEDs for full blown SPS tanks and everyone doesn't need it. Then, you compare to a 400W plus 2 T5s lighting, what I certainly would consider lighting for a full blown SPS tank. Unless you can produce PAR numbers that 36 LEDs are equivalent to 400W plus 2T5s, this is a wholly skewed apples to oranges comparison.

There's perfect logic in my comparison. If I didn't have my LED light, I'd be using a 400w MH setup. What's the problem? If it makes more sense to you, substitute 400 for 250. Bulb cost is same but electricity usage is lower. I can grow SPS easily with my LED system.

I wasn't suggesting that people are getting too many LED's for a full blown sps system, but for the normal corals that the majority of people grow.