Switching from LED to Metal Halide

[mcarroll]

Anyone know how to send a PM to @Wankell?

 

[saltyfilmfolks]

Ok, regarding lux meters to compare lighting when switching from one to another...if MH is giving me 40,000-60,000 lux on average in the main areas of the tank (not around the edges), and LED is giving me 25,000-35,000 lux in the brightest areas, is this comparable? Are you aiming for the same lux numbers from both systems or is there a conversion factor? (I think there is but I can't recall exactly). @mcarroll @saltyfilmfolks

There was an odd superstition that led were More"par powerful" and I have no idea where that came from. Perhaps it's becuse you need more intensity with led. Dunno.

The lux /=par constant for some mh is between 40 and 50.
For led 60 and 70.

I use 50 typically for MH and am generally pretty close.
60 for led.

So at the same lux (brightness) mh has more par

 

[saltyfilmfolks]

Grandis, you are exactly right. My first run with LEDs I tried it like they had at the shop, very blue. LOL.

I do think part of the trouble with LED is that you can adjust too much and the average reefer probably shouldn't.

That's right there. Everybody turns them down. Then pretends they know a lot about the spectrum corals need. And cool white is bad. Cool white is mostly blue. Lol.

 

[KJoFan]

There was an odd superstition that led were More"par powerful" and I have no idea where that came from. Perhaps it's becuse you need more intensity with led. Dunno.

The lux /=par constant for some mh is between 40 and 50.
For led 60 and 70.

I use 50 typically for MH and am generally pretty close.
60 for led.

So at the same lux (brightness) mh has more par

I just didn't want to be frying my sps going from MH to LED at those lux values and not know it until it was too late. But...seems like if anything they are "underlit" compared to MH.

 

[dricc]

I'm with you, there are so many variables it's a bit silly to bicker back and forth about it. I also had a 6 lamp but it was a 48" and I didn't use the house AC to help cool the tank. Which would be another variable!

Preference, preference, preference, there's no longer an argument that LED doesn't work, so at the end of the day does it really matter? Why don't we tear each other apart about what cars we drive instead? ;Yuck

You should see my awesome Yugo.

 

[saltyfilmfolks]

I just didn't want to be frying my sps going from MH to LED at those lux values and not know it until it was too late. But...seems like if anything they are "underlit" compared to MH.

Yep. Good call. There are some that still claim that they had issue even with matched par numbers. But....that was usually growth or color related. Or The Who knows category. I personally would try to match numbers and start lower to acclimate. and watch the coral.

 

[mcarroll]

There was an odd superstition that led were More"par powerful" and I have no idea where that came from.

I'm not sure either, but that kinda meshes with the fact that blue wavelengths carry more energy, but yet are not "more photosynthetic". Maybe related?

 

[KJoFan]

Yep. Good call. There are some that still claim that they had issue even with matched par numbers. But....that was usually growth or color related. Or The Who knows category. I personally would try to match numbers and start lower to acclimate. and watch the coral.

This is a QT tank all sps had to go into for the next...couple months. So this won't be a long term situation and being a bit underlit for that time will be better than too much.

 

[mcarroll]

Yep. Good call. There are some that still claim that they had issue even with matched par numbers. But....that was usually growth or color related. Or The Who knows category. I personally would try to match numbers and start lower to acclimate. and watch the coral.

Agreed!

When I switched to LED (sans meter) I dropped from around 60,000+ lux to around 14,000 lux.

That big a drop in the new tank will be a problem. Proof positive.

Other than my example, all other problems from switching lights that I've heard are from increases in lighting....I think the side-effects on the coral animal from increasing must be stronger, or something that (some) tank-raise corals are more susceptible to.

@KJoFan If you're close to matching lux between the two systems and err on the side of conservancy with a slightly lower number in the new system, you'll be pretty safe.

 

[KJoFan]

Agreed!

When I switched to LED (sans meter) I dropped from around 60,000+ lux to around 14,000 lux.

That big a drop in the new tank will be a problem. Proof positive.

Other than my example, all other problems from switching lights that I've heard are from increases in lighting....I think the side-effects on the coral animal from increasing must be stronger, or something that (some) tank-raise corals are more susceptible to.

@KJoFan If you're close to matching lux between the two systems and err on the side of conservancy with a slightly lower number in the new system, you'll be pretty safe.

Blue channels are at 80% at the current lux values I posted so...chances are even if I maxed out those channels I would be fine. But, I'll leave it for now knowing the corals more than likely are just fine.

 

[rtparty]

I think one could only say that without a lot of first hand experience. While my tank was on a 12-hour schedule, corals would decline at the 6-month mark like it was clockwork. When I cut the lighting hours back thanks to the concept of Peak Sun Hours (I think at least analogous to DLI)...

...the clockwork responded predicatably and corals would decline at about 9 months.

Likewise, the level of brightness between old and new bulbs wasn't debateable....old bulbs were MUCH less bright even to the naked eye. Having a dual halide fixture makes this easy to see – switch one bulb and not the other and you get a direct A-B comparison so your brain's interpretation is trustworthy. Newer bulbs were BRIGHT!!!

Last, old bulbs LOOKED WORN OUT. The amount of carbon scoring inside the bulb always seemed phenomenal to me.

If you wanted to say that there were some tanks and some corals that could tolerate this, I'd be willing to listen and hear specifics – including what tank, what light, how high, what corals, and tank water test history.

As a general statement about all tanks, lights and corals I call one bee to be followed closely by one esse. [emoji14]



If you're looking for a tiny bit of savings switch to DC pumps. [emoji14]

Up Front Costs
When you (or I; anyone!) can build a perfectly valid LED fixture for less than the cost of a set of new mercury-based bulbs, I think you have to consider that. Comparisons are almost always with the highest end commercial fixtures – which I understand, but which doesn't tell the whole story.

At my DIY rate I could build a new LED fixture, use it for a year and then throw it in the trash and build another one next year and STILL COME OUT AHEAD. That's big potential savings, not tiny.

Bulb Costs
And unless you are willing to revert to Chinese no-name bulbs and pay almost nothing for power, you'll notice a bigger-than-tiny potential savings in ongoing costs as well.

If you haven't run the numbers, you should just to know for reference....it's big.

Power Costs
If you're in a hot weather state and/or an expensive electricity state, then there's even more potential as you might eliminate a chiller in the process, or at least take it from running all the time to running rarely. It makes a big difference!

In a cold room, the heater will have to work harder and harder with each efficiency improvement to keep the water tropical, which will cause the HVAC to work a little harder to keep the house cool. Bye-bye power savings in that case.

After swapping out halides for LED (300 down to 40 watts) and a Mag 7-based skimmer for a Tunze 9410 (70 down to 14 watts) I had to add two large heaters to keep the tank steady during the coldest winter months.

That said, potential is potential and nothing more – you might not net anything more in ongoing cost savings than the up-front costs.

You have to look at the details of your own case to know.



For these purposes you just want the numbers close – no conversion to any other units is necessary. You could say the LED's are giving you roughly half the power in the tank as the halide system. (Helpful to remember these numbers are always rough and they don't need to be exact.)



In hot climates it's not uncommon though....or anywhere the HVAC doesn't keep a steady 72ºF all year round.

That's fine if you think I don't have first hand experience. I don't care to get into a debate about it. I know how long I've run halides before replacing and how my tanks reacted. I have never seen a decline at 6 months or 9 months due to lights. Granted the tanks I ran halides on didn't contain the super elusive, hard to keep, beyond sensitive corals. Most my SPS were the "weeds" of SPS. I was just starting out with SPS. Green Slimer, Monti caps, birdsnest. I then got confidence and started added ORA pieces. Pearlberry, Joe the Coral. Got some different millis and then upgraded to a larger tank. That's when I went to an ATI Sunpower from the Hamilton Bimini running a Phoenix 150w. That Phoenix bulb was over 2 years old and the tank was thriving still.

 

[mcarroll]

There's still a difference between none, some and a lot, right? I never had fancy corals either...once you introduce mushrooms as a "beginner coral" that ship has sailed. My mushrooms were attracted to acro frags like flies to poo – stung every one to death before they could even put on an inch. So lotsa cap's, digi's and birdsnests....a few others like Favia and Hydnophora. I'll probably take another try at acros someday when I upgrade from my current tank

All I was saying I guess is that if you do have experience, then I'd like to hear the details. (I did say that, BTW.) I have some evidence that it's not a "total myth".

Beginner corals – now there's a total myth!!

 

[A. grandis]

Total myth that halides should be replaced that often. Quite a few studies and tests show that there is very little spectral change and/or PAR drop even after 24 months with most halides.

What will really shock people (it certainly shocked me) is BRS' T5 testing where an 18 month old bulb had the exact same spectrum as a brand new bulb. I've spent years and years testing T5s and relaying info over on RC. Unfortunately, I never tested the spectrum (didn't have the tools or money) since even the professionals accepted T5 bulbs shifted after about 9-12 months. If that "theory" is debunked, it just killed another common myth: that LEDs save everyone money.

That' very interesting!
Would you please give us those sources? links?
Thanks!!
Grandis.

 

[saltyfilmfolks]

That' very interesting!
Would you please give us those sources? links?
Thanks!!
Grandis.

I'd like to see that too.

 

[rtparty]

That' very interesting!
Would you please give us those sources? links?
Thanks!!
Grandis.

To the halides or T5s?

The halide study I read was in Advanced Aquarist or Reefkeeping Magazine and I couldn't find it all morning. Basically they took 4 new bulbs and (4) 1 year old bulbs and tracked them monthly for a year. I want to say there was less than a 10% PAR drop from months 6 to 24. Some think that's a lot but for me it's not worth changing bulbs over.

As for the T5s, Ryan posted that in the T5 cooling thread and said they will have a video in the future going over it. Maybe he can chime in here? @Ryanbrs

 

[mcarroll]

Definitely would be interesting to see. I wish I was using my lux meter back then so I could add more specifics about "how much dimmer" at least....all I have was the coral reactions (I think it was always the M. cap's that reacted too now that I think back.) and visual cues to relate, unfortunately.

 

[A. grandis]

To the halides or T5s?

The halide study I read was in Advanced Aquarist or Reefkeeping Magazine and I couldn't find it all morning. Basically they took 4 new bulbs and (4) 1 year old bulbs and tracked them monthly for a year. I want to say there was less than a 10% PAR drop from months 6 to 24. Some think that's a lot but for me it's not worth changing bulbs over.

As for the T5s, Ryan posted that in the T5 cooling thread and said they will have a video in the future going over it. Maybe he can chime in here? @Ryanbrs

I was thinking about the halides. I'll try find when I have an extra time...
If someone finds first, please post link here.
Thanks very much!
Grandis.

 

[Ryanbrs]

To the halides or T5s?

The halide study I read was in Advanced Aquarist or Reefkeeping Magazine and I couldn't find it all morning. Basically they took 4 new bulbs and (4) 1 year old bulbs and tracked them monthly for a year. I want to say there was less than a 10% PAR drop from months 6 to 24. Some think that's a lot but for me it's not worth changing bulbs over.

As for the T5s, Ryan posted that in the T5 cooling thread and said they will have a video in the future going over it. Maybe he can chime in here? @Ryanbrs

I read the same thing which made me wonder about t5's. Once we tested some year old t5s and they matched the same spectrum as brand new I had to find out. I think we are a couple months from sharing results.

 

[jda]

I change my Radiums every year and 14K Phoenix every other year on Valentines day. If you were at my house the week before and then the week after, you would never be able to tell the difference. The cost of replacing these sooner would no problem for me, so know that money has nothing to do with why I run them this long. When I overdrove XM/Hammy 10K on M80 (awesome output and color) and Radium 20K on 400W HQI, then it was 9 months and I absolutely could tell a difference in color when I put the new bulbs on.

Of the 22-25 guys that I know that run high end Acropora tanks like mine, only two of them use LEDs are primary and both do not use any name brand. 7 or 8 are back to T5/Radiums from Radions. 10K, 15K Ushio and 20K Radiums with some T5s or Reefbrites are the most used - I am somewhat in the minority with 14K Phoenix HQI. I know really, really well that what I am into is a more a niche than mainstream, but please be cautious when commenting about market share - nobody truly knows anything about this and it varies drastically from niche to niche. FWIW - I go into about 30 homes a week and see a few dozen reef tanks a year - the VAST majority have some GPS, mushrooms and run years-old T5s or PC that they got at Petco and would never think about even looking at a message board.

 

[alton]

FWIW - When I ran MH I ran Coral Vue 12K Reeflux first then moved to Radium and then finishing up with Phoenix 14K SE. Radium, CV, and Phoenix averaged 18 months dropping 10%. I did have one Radium go 24+ months, and one that dropped 10% at 12 months. When fellow reefers came over they could not tell the difference between the Phoenix SE and the Radium lamps side by side or the difference between a new lamp and the 24 month lamp. Only by using a meter could the difference be shown. When I switched to all LED my benefits where the fact I could now install glass tops slowing my evaporation down from 10+ gallons a week on my 300 to 2 on my 180. In the many years of keeping MH I had to replace my AC fan motor twice at $500 a pop, the AC tech blamed the aquarium. The biggest benefit was the clean look versus the big bulky look of the MH pendants that stood 8" off of the top of the tank(see below). Electrical savings ? None! In the summer I would cut my MH halides back to 3 to 4 Hours a day with two BML leds running at 9 hours a day, in the winter MH ran 8 to 9 hours using them as heaters as well. Now I run 4 BML Leds at 8 to 9 hours everyday and now have to add a heater in

the winter. Coral growth still about the same, my caps and bird nest did grow faster under MH, everything else about the same.