OK - here's a question for you. I've decided it's time to upgrade my lights. I am currently using 576 watts of PCs over a 240 tank. Don't laugh - I'm getting unbelievable growth, even from the few SPS corals in there (I know, there is no LPS or SPS classifications, old habbits die hard!) But like many in the hobby who start with sofities and get bitten by the acropora bug (no pun intended) - I see this coming for myself.

So I'm debating between T5HO, LED (hi Carmie!) or good old fashioned metal halide. My tank is acrylic. It was custom made, and instead of the usual 3-4 small openings on the top, I had it made with 2 larger ones. This way I could get larger pieces of live rock in there. The two openings are 2' wide, and each is 1' in from each side of the tank. This leaves a 2' section that is not open in the middle of the tank.

When discussing this with the manager of a LFS, he told me NOT to use MH lights over this center section, as the heat would cause the acrylic to harden, dry, get brittle, and potentially crack. So my question is this - any one else using metal halide over the unopen portion of their acrylic tanks? My plan was to use 250 watt bulbs x 3, leaving the center bulb over the acrylic. I would modify my canopy by removing the top sections (the entire top opens up and is in two separate sections.) Beause the stand is rather high, the lights could sit 5 - 6 inches from the top of the tank and still not be visible. This would also allow the heat to freely rise away from the canopy.

Thoughts?

i would think that the LFS manager is right. the halides could even melt the acrylic (but i am not sure). i know that it can melt the plastic brace on a 4 or 6 foot tank. i would go with the halides on the ends and T5's in the middle. just finding the color combo for the T5's could be difficult to match to the halides though.

Yep, I'd go with the LED. :)

There's a real possibility of the MHs turning the Acrylic's composition to something that would soften it when they are on to hardening it and having a failure in any event. It isn't worth the risk. More and more people are turning to the new technology of LEDs with no heat transfer to the aquarium, 40% energy savings and total computer control of the color temperature.

I've been fortunate enough to have used PFO's G series then the H4 series and soon the I4 series LED lights. I love them and highly recommend you consider them.

Dick

Thank you all for the advice. I agree that halides over the acrylic portion would eventually have detrimental effects over time.

I beleive I have convinced my wife on the benefits, and eventual cost savings, of LED lights. Will update you when I finally decide. Thanks again.

OK - I'm sold on LED. That took less than one hour of research!

Questions:

Can anyone tell me the difference between the H4 series PFO lights and the new I4 series? There may be some good deals on the H series with the relaese of the I series.

Since my tank is 8' in length, should I go with the 72" model, or (2) 48"? Note: I keep my corals and live rocks away from the sides of the tank to assist in cleaning and water flow, so I'm think the 72" should be fine.

Thanks for any and all input.

Dana

Good decision! I don't think that you will regret it at all! My tank is 23" deep and I am very pleased with the growth and coloration of my corals and I have the G series. I think that I read somewhere that the I series is 40% brighter. I am sure that Dick knows and I bet he will check in soon.

At MACNA, Dana Riddle said that we often over light our corals. He is supposed to be publishing this study shortly.

Thanks Carmie,

Yes - I have read a few articles that speculate that many tanks suffer from too much lighting, and that the old theory that you can never have too much light is not true.

I will continue to look for information comparing the two models. I do know that PFO specs a different color temp for the two models, which seems odd since it is my undersatanding that you can vary the color temp. Maybe it's the DEFAULT color temp.

Could be. Or it is the maximum intensity.

OK - I'm sold on LED. That took less than one hour of research!

Questions:

Can anyone tell me the difference between the H4 series PFO lights and the new I4 series? There may be some good deals on the H series with the release of the I series.

Since my tank is 8' in length, should I go with the 72" model, or (2) 48"? Note: I keep my corals and live rocks away from the sides of the tank to assist in cleaning and water flow, so I'm think the 72" should be fine.

Thanks for any and all input.

DanaDana,

The difference between the H4 and the I4 is the I series will have the latest in 4 watt next generation LEDs, producing 30% more light than the H series. They are considered to be equivalent to 400W 15K MHs, without generating the heat of the MH. Here's a link to the I4 specifications, I4 Specs (http://www.theculturedreef.com/i4specs.htm).

As far as which length to buy for your 96" tank. That is a decision only you can make. Here is the difference as I see it. The major difference I saw between MH and LED lighting is that MH bulbs are omni-directional (spreading light in all directions) and the LEDs cast their light straight down. PFO has added a lens that spreads the light somewhat but their ability to spread light is limited. You have to judge for yourself if the amount of space you left for cleaning will be adversely affected by the 72" model. The end banks of 25 LED lights are setback about 3" from the end giving you not 12" of dimly lit area but 15". Personally, I'd recommend the 48" lights.

The default color temp for the H4 is 20K and the I4 is 15K but, both are adjustable from around 10K to 20K, if I remember correctly. Most people adjust them to suit their eye appeal and the corals seem not to mind.

I have to caution you about availability. This coming shipment is nearly sold out. The next shipment is not due in until the end of December of first of January. The reason for this time delay is complicated to explain but picture this...each separate component must be ordered anywhere from 2 to 3 months in advance from several different manufacturers in several different countries. Pat has to coordinate the arrival of all parts to reach the China factory, where the unit is then assembled for shipment to PFO. It's more convoluted than that but, you get the idea.

Dana, I'm sending you a PM.

Dick

Amphibious, quick question for you, has PFO got QC under control with the I series, I have done alot of reading on the forums and such and I am convienced that LED is the way to go, the only problem being is the quailty of the lights, I know that Pat stands by his product completely, but still, if I am putting out that kind of money I feel I should not have to mess with them AT ALL.... unpack plug in and play! I hear that AI is doing a 24 burn on the lights they ship, and by the looks of it they have almost the same system as Solaris. I guess I am looking for a little reassurance that the Solaris LED has gained control on quality and that I will have spent my money for a quality product.

Hey putter,

The short answer is yes. The longer answer is the I series haven't arrived yet. They are due any day and will be shipped after PFO does their QC by burning them in. The early problems with the G series was mostly attributed to Pat designing them in Imperial measurements and the Chinese working with Metric. A stupid mistake that cost Pat a bundle but it has been corrected. I have the H series running since June with out any problems. anxiously waiting the arrival of my I series. It is true that Pat stands behind his products 110%.

Yep is one thing for sure I have gotten out of all the research is that he stands by it completly, so with your answer and the lack of info on the AI system, I think I will put myself on the list. What's your price on a 48" I4?

putter, welcome to TR.

I sent you a PM.

Dick

I'm trying to figure out why this conversation is PC vs MH or LED and T5 has been completely dismissed.

One of the most beautiful tanks I have ever seen was a friend's who used T5 exclusively.

Now don't get me wrong, the LED hoods are really amazing, but expensive as hell - and it was my understanding that the LED arrays did put off a good deal of heat, although I could be wrong on that one.

I'm trying to figure out why this conversation is PC vs MH or LED and T5 has been completely dismissed.

One of the most beautiful tanks I have ever seen was a friend's who used T5 exclusively.

Now don't get me wrong, the LED hoods are really amazing, but expensive as hell - and it was my understanding that the LED arrays did put off a good deal of heat, although I could be wrong on that one.
The LED arrays put out a small amount of heat compared to all other forms of lighting used in reefing. They are designed with a heat sink above the LEDs to draw that heat away from the display tank. Then vented out the ends with fans.

Dick

OK, so the LED arrays aren't hot. If they are fan cooled, I see where evaporation could be a problem.

But the price issue cannot be dismissed.

Again, don't get me wrong, they are VERY cool. Just pricey as heck.

If it was my tank, and I HADN'T just won the lottery, I would probably go the T5 route. If you would like I would be happy to post some photos of what this guy's tank was like.

OK, so the LED arrays aren't hot. If they are fan cooled, I see where evaporation could be a problem.

How would evaporation be a problem???

I'm trying to figure out why this conversation is PC vs MH or LED and T5 has been completely dismissed.

One of the most beautiful tanks I have ever seen was a friend's who used T5 exclusively.

Now don't get me wrong, the LED hoods are really amazing, but expensive as hell - and it was my understanding that the LED arrays did put off a good deal of heat, although I could be wrong on that one.

This conversation started out with me expressing concerns about upgrading my PC lights to MH lights over my 240 acrylic tank. It was not to blast, or ignor, T5 lights. I have T5s over my 180 and like them very much. I had just heard rumors about using MH lights directly over the closed acrylic portion of my tank, and how it could cause the acylic to fail.

LED came into play as it is the only light source currently available that does not increase the temp of the water. I agree that they are very expensive. But when you factor in the energy savings, the elimation of a chiller, and the fact that the bulbs last 10 - 15 years - they really are quite reasonable. Your just paying for the cost up front.