Help, they are laughing at me Anthony :)

[alexinfla]

Hello kind sir,

I saw you talk at MACNA last week in DC, and I remember you mentioning something about eggcrate having 2 sides, where one can actually increase light (think you used a "roughly 20%" figure).

Anyhow, am I remembering correctly, or did the wine take it's toll? :)

[RGibson]

alexinfla there are two side to the eggcrate .

[Anthony Calfo]

yep... I used a close up picture to show the "thick" versus "thin" sides of the partitions which are used to spread or focus the light as you need/see fit.

Turn off your room light sand leave only the tank light on... then flip a sheet of egg-grate back and forth. You will see the difference in light spread (vis a vis light shed/wasted on floor out of/in front of the tank... versus not at all when all is focussed down/in.)

[Daemonfly]

Interesting. I always figured the difference was just due to manufacturing process.

[alexinfla]

Thanks for clearing that one up.

[Jamesurq]

Originally posted by alexinfla
, where one can actually increase light (think you used a "roughly 20%" figure).

Surely it increases dispersion of the light by a certain percentage - but boosting overal output by 20%?

[Steven Pro]

I believe it was Dana Riddle that first suggested this at the 2nd Louisville MACNA. You might be able to find more information using a search engine with his name and eggcrate.

[Anthony Calfo]

Jamesurq... if you will take a look yourself (light meter aside even)... can you explain where the 9, 12 or even 16" of light spilled onto the floor in front of the aquarium is going when you add a focus-side sheet of egg-grate over your... say, 18" wide aquarium? Its... er... getting redirected somewhere :D

And yes... Dana was one of the folks that took the time to do proper measurements.

to All/at large - rather than be skeptical folks... do spend $9 on a sheet of egg-grate for your multi-thousand dollar reef systems and see for yourself. I promise its worth it.

C'mon... put the crow bar in your wallet, or just bid lower on your next designer label coral frag :p You'll get far more mileage/benefit out of the lighting tip than the coral frag anyways.

Anth- :)

[RGibson]

Anthony were can we fine the info on Dana measurements?

[diverrad]

hey James:wave:

the egg crate does focus the light do an experiment and see for yourself, it really does work.

[Jamesurq]

Originally posted by Anthony Calfo
Jamesurq... if you will take a look yourself (light meter aside even)... can you explain where the 9, 12 or even 16" of light spilled onto the floor in front of the aquarium is going when you add a focus-side sheet of egg-grate over your... say, 18" wide aquarium? Its... er... getting redirected somewhere :D


Redirected, yes - dispursed, yes... But increased output of 20%? It's making the light spread larger (or smaller if you flip it) but it's not multiplying the overall power of the bulbs is it?

How is that possible?

[Jamesurq]

Not saying it's NOT possible - just finding it hard to fathom.

Something for nothing....

[Anthony Calfo]

test it yourself or dig for the data James... I did.

Make us proud... or at least let's stop waxing philosophically/bantering ;)

[Daemonfly]

Guess I'll test it out as well. Got a cheap, yet somewhat popular LUX meter at home.

Only thing I was considering is that the eggcrate would block some of the light from getting into the tank. Would it's redirection of light still be beneficial vs any light blocked? Guess I'll have to test to find out.

[Jamesurq]

Ok - I'll stop waxing philosphically... How about I point you to some links:

http://www.paralite.net/plastic_louvers.htm
Indicates a 75% light transmission from plastic eggcrates - ie: 25% loss of light.

Here's an interesting one - it talks about parabolic louvers - the eggcrate's bigger brother:

http://www.eclipselightinginc.com/pdf/Parabol.pdf
Look at lumens across all angles in LSI test 18705 and 18706 and LSI 18746 and 47 respectively which are the same bulb but with a specular parabolic louver and without...

I'm not an expert by any means - in fact I know very little aside from what I just read for a half hour or so. But in my 30 minutes of digging I couldn't find ONE "eggcrate" manufacturer that stated that their products increased light output. It seems to me that they'd be jumping up and down to say that... What they were saying was that it dispurses the light more evenly and the effective light at the wider angles from the bulb is more... But not that the output of the fixture itself is increased. I suppose if you were running flouresent bulbs with no canopy, the light that would have been reflected onto the floor, would potentially be pushed straight down into the tank - but I'm not sure I know of anyone that runs that way... Basically, I would think that the 25% loss that you took from the shading caused by the eggcrate would far outweigh any potential benefits of a slightly more focused beam... But I could be completely wrong.

Sorry if this get's on your case Anthony.>> I guess your "make us proud" comment or potentially your plea for me to stop bantering incited me to stop in and do some digging. My sources aren't exactly scientific papers, but google felt they were important :)

For what it's worth - I did go out and put a piece of eggcrate under a double NO fixture just now and visually I noticed LESS light coming through. But then again - my eyes are not light meters...

Hope you take this the right way - I've just never been the type to take something that to me sounds a little hard to swallow and believe it.

After doing some additional reading - lots of it.. and doing a couple visual experiments (albeit very late at night ;)) I have a tough time agreeing with you.

Is that okay?

Sorry man.

[PUGroyale]

Originally posted by Anthony Calfo
to All/at large - rather than be skeptical folks... do spend $9 on a sheet of egg-grate for your multi-thousand dollar reef systems and see for yourself. I promise its worth it.

C'mon... put the crow bar in your wallet, or just bid lower on your next designer label coral frag :p You'll get far more mileage/benefit out of the lighting tip than the coral frag anyways.

Anth- :)

Considering placing anything between the lights and the tank [with the exception of prism maybe] could only act as an impediment... I find your comments not only unnecessarily glib, but also embarassingly incorrect.

[Steven Pro]

James, the difference I can see in the data you present is the manufacturers are talking about lighting a room. Of course you won't see an increase in light intensity there. The room is far too large, But, if you take light that would have been scattered all over a room and focus it into a small area (say an aquarium), then you will see a localize increase in light intensity while the rest of the room will now appear darker. This is the exact same theory we see everyday in reflectors. Good ones (like Diamond Lumenarc for example) can increase the effective amount of light going into the tank dramatically over lesser reflectors.

[Jamesurq]

Lumenarc reflectors take the light that would have been pushed up and to the sides and force that light down - they wrap around the back side of the bulb. I understand your comparison though - and I definitely understand the concept that Anthony is putting across - I just happen to think that although you potentially take a small portion of the light that could have spilled out through the front glass and direct it into the tank, your overall loss of approximately 25% of the output of the lighting right from the start outweighs that.

I could be wrong...

[gobygoby]

what about reflective egg crate, this silver ones.....does the reflective coating flake off over time? or has no one really ever used it?

Goby

[Anthony Calfo]

I e-mailed Dane (Ridle) at his lab... he just flew back home from a long trip but will dig for his data shortly he says. I'll post promptly when so.

The gist of the issue here is that the (improved) focus of light by the egg-grate offsets the (minimal) loss off light blocked by its thin profile.

Put another way... the loss of light from (typical) spread is reduced significantly by the use of a focussing grid ala egg-grate.

Indeed... I have the same perspective as Steve here, too, regarding the above listed sites/info:

The only thing that matters re: this topic is the light making it into the aquarium. And if you'd take a light meter... ahem ;)

James... very good to see you dig for the data. Obviously, it chides me when clearly intelligent people rest easy and play armchair QB or seem to want to be enabled.

To be clear though... I did not think you were so much of either... rather, I thought (seeing other posts by you) that you were at least occasioanlly a troll (see BB lingo/dictionary for def if needed). Its a style of message board participation that I do not have very high regard for. Just my opinion... I could be wrong.

[PUGroyale]

Originally posted by Anthony Calfo
The gist of the issue here is that the (improved) focus of light by the egg-grate offsets the (minimal) loss off light blocked by its thin profile.

Put another way... the loss of light from (typical) spread is reduced significantly by the use of a focussing grid ala egg-grate.



Are you talking about putting the eggcrate on top of the tank or on the bottom of the fixture? I guess I could see how it might work if it was on the bottom of the fixture by focusing angled light that would otherwise escape downward. Is this what you mean? Sorry about my previous post. Yours seemed a little sarcastic though. ;)

edit: what if I made an eggcrate border of say three rows of the squares that encircled? [ensquared :lol:] the perimeter of the fixture but left the middle open? Any thoughts?

[Jamesurq]

"it chides me when clearly intelligent people rest easy and play armchair QB" "I did not think you were so much of either"

Ok - so you basically just told me you think I'm stupid and that I'm a troll.

"I could be wrong" doesn't discount the insult as much as you would like it to.

[Anthony Calfo]

No worries Dave... I often allow my dry wit to stray sarcastically. Glib, sarcastic... all true at times. Your read is/was fine by me. I do hope to take as well as I give :p

You make an excellent point: indeed... for folks with halide fixtures that are rather high off the water, the egg-grate or like apparatus would need to be under the canopy itself just at (or only slightly beyond) the extension of the reflector to focus more of the light downward.

But for folks using fluorescents... the egg-grate can simply rest on top of the aquarium since fluorescent lamps themselves need to be very(!) close to the water (no exaggeration here... anything more than 2-3" off the surface of the water with fluorescents is a serious loss of light (intensity). Truly severe... the light meter does not lie ;)

[Anthony Calfo]

naaaa.. not 'stupid and a troll', James... 'lazy and a troll' :p

I know that you are quite intelligent and I said so above.

But if you make a habit of stirring the pot for the sake of stirring the pot (posts for your own pleasure... hence the troll remark) with comments that don't amount to much more than pot shots without backing them up... you may need to concede that I (others) could be right. Or... maybe I'm just not reading your best work :D

I must admit, you are not reading mine right now. :(

I do apologize for that.

But I also will not pull punches on wasteful behaviors/posts... sigh... as this very one of my own has become.

Please make your parting comments James and it can/will rest there if you'll kindly let it.

[CH]

You say anything more than 2-3" off the water for fluorescents is a serious loss in intensity. I agree this is probably true, and have often wondered how much better my lighting would be if I could move it closer to the water. Right now, my lights (VHO) are about 8" from the water. It's hard to move them any closer, just because of the way the hood is made (I wouldn't have room to get my hand in the tank with the lights lower) but i know I would be better off if I could. Do you think if I were to mount a piece of eggcrate right up under the bulbs, it would help significantly? In theory it seems like it would, but I'm thinking I still need to lower the bulbs somehow (maybe I need a contraption for raising and lowering!)

[gobygoby]

part 1.
Has anyone used the reflective egg grate? and does the reflective material flake off after time?

part 2
In laymens terms(IE: yes or no, for us idiots) is putting the grate worth it, or is it just for fun. I mean does it really matter?

Thanks!
Goby

[Anthony Calfo]

Hmmm... tough to say on the higher mount fluorescents. At issue is the type of lamps (NO, VHO, PC, T5) and their intensity with additional consideration for their age. While more light can be focussed by using the egg-grate here... my bigger fear is that the height of the lamps off the water is unduly handicapping you above all. It really is a big deal. I've heardsome (reef) lighting experts say that if the fluorescent lamps are higher than 3" off the water, they are doing little more than aesthetics :(

Testing my own lamps through the years... the drop inch after inch from the lamp on the approach to the water alone was amazing (in a bad way :D)

[Anthony Calfo]

the reflective egg-grate is used by aquarists... but the coating does not hold up over time very well.

As for the value of using egg-grate or not, I obviously (as stated previously, believe that there is a net benefit with it. I'll post data from Riddle laboratories as soon as I get it.

[CH]

That was my fear. I kind of always knew I needed to lower them, but everything has been doing good, including some Montipora. I would expect though that things will start doing great (as opposed to good) if I lowered them, especially considering its a 75 gallon with 3 - 48" VHO bulbs (330W) - not a ton of light to begin with.

So does anyone out there have a fancy contraption or idea to keep the lights low, but then raise them when I need access?

[Jamesurq]

Originally posted by Anthony Calfo
maybe I'm just not reading your best work :D

Please make your parting comments James and it can/will rest there if you'll kindly let it.

Probably :)

No need for parting comments.

BACK ON TOPIC:

I did some searching on Dana's original work and from what I'm inferring the biggest part of the added light equation is that the light that normally hits the water at a 45 degree angle would be reflected OFF the surface of the water. With the eggcrate, the light doesn't reflect as much.

Not sure why you just didn't say that in the first place... making me have to actually research and read stuff... jeez... and you said I was lazy ;)

[captbunzo]

Ok, maybe I am little bit lost here. Maybe someone can clarify some things for me:

1. What exactly is a troll?
2. What do you feed one?
3. Does it have a certain set of lighting requirements?
4. Will it eat my favorite [FILL IN THE BLANK]?
5. If it gets stuck in my protein skimmer, will my tank overflow or explode?
6. And most importantly, if I have a dark, blurry picture of one, can you please tell me what species it is?

Sorry, I just couldn't help myself........ :D

(disclaimer added: This post was meant to cause offense to nobody - or perhaps everybody, I don't really remember. There must be another hermit crab stuck in my ear. Hmmnn..... The diatoms! GOD HELP US!!! THE DIATOMS ARE BACK!!! Ahhhhhhhh... Gurgle gurgle gurgle...)

[Steven Pro]

Just as a second opinion, I used the silver eggcrate for almost two years without flaking before changing my lighting around, part of which consisted of better reflectors so the eggcrate was less necessary. I did not experience any flaking. Perhaps I got a particularly good piece. I don't know if the silver is any better at focusing the light versus the cheaper white though, but it is shiny and sexy looking. Sort of like a champagne colored Lincoln with gold trim accents. :D

[Puffer Queen]

Got to love those lincolns Steve - you have one on order, right?

Kelly

[ktani]

you people are sick. There is nothing sexier than a hot red Yugo.

Now we are talking sweet. :-)

Seriously, I am going with the Diamond Lumenarcs and was thinking of not using eggcrate. Thoughts?

Also, it was great to see everyone at MACNA and also Steve, was a great privilege meeting you and hearing your excellent presentation.

Thanks.

Kip

[Anthony Calfo]

a fast response from Dana (big thanks to him for the effort in a very busy schedule of his own!)

but the gist of it is as we (proponents) remembered:

- his charts show an increase of 25% in the focussing area
- the egg-grate (parabolic louver) must be positioned properly: 2.5-3" from the pointsource of light/halides
- he did not see any significant improvement with fluorescents high off the water
- the egg-grate (obviously) does block some light

And (my) Cliff's notes version of the topic is (still) the same: egg-grate under typical/practical applications is a net benefit overall to most aquarists.

Plus it keeps more of your fairy wrasses inside of the tank ;)

Paul... special thanks for the levity :p

[captbunzo]

Ok - for a serious question - how does this compare with using glass?

[ktani]

Anthony,

is the implication then that the flourescents do little for the corals except perhaps flourescence?

Also, if the distance is increased, say for example by using the Lumenarcs does that negate some of the value?

Thanks.

Kip

[Anthony Calfo]

glass somewhat to significantly reduces light (variously depending on the type of glass... some total light/intensity... others selective for X wavelegths/UV, etc.). All glass is not equal by any stretch of the imagination. Its not all bad either. Some glass lenses are needed under some lamps and/or over some corals to filter, eg, excessive UV. No easy answer here.

[Anthony Calfo]

another tough one Kip... fluorescents run the gamut in potential relative to type (NO to T5 and everything in between... SHO, VHO, PC), age of lamps... then slight impediments which severely reduce output (more than with halogens) such as salt creep, dust, debris... discoloration to the water.

Overall though... we know that halides have the best punch/penetration generally for amount of light penetrating the water at depth relative to watts consumed.

And we knw that it takes little to negate most fo the value of most fluorescent style lamps such as age over 6 months old, thick plate glass lenses/canopies, height over 3" off the water or any visible discoloration to the water. All severe handicaps to the amount of useful light produced versus watts of electricty consumed.

That all said... and presuming your lamps fit any of the above common scenarios, I'd say that yes... typical flourescents are "poor values" and even fab reflectors will not change that. Such flourescent lamps are aesthetics at that point.

[Jamesurq]

Originally posted by Anthony Calfo
- his charts show an increase of 25% in the focussing area


I'm having trouble figuring out this statement.

Is he saying that the area of focused light was increased by 25% or in a specific area of focus the actualy intensity was 25% higher?

Assuming it's the 2nd interpretation - did he say where that area of focus was?

[Steven Pro]

It should be the latter, the intensity of light in a given area increased 25%. And I believe that area was the test 'tank' (I am unsure if this was done on a real aquarium or simply a marked off area similar in size to an aquarium).

[Jamesurq]

But a specific area of the tank?

I think that what we're seeing here is an increase in intensity in the areas that normally wouldn't be as brightly lit because of the reflective qualities of the water's surface eg. the front 6 inches of a 24 inch deep tank.

The areas directly under the point source lighting should have a lower output. Due to the "the egg-grate (obviously) does block some light" statement from Dana.

To say that it increases the intensity of light by 25% is a little misleading I think. Because actually while increasing it by 25% in the "focused area" you're decreasing it by at least that much in the areas directly under the bulb.

Interesting topic.

[Steven Pro]

I believe it was an overall number. That over the entire area, there was a 25% increase in intensity

[DitchPlains2]

what is this thread about? I followed the links but havent the foggiest about eggcrates? Do you mean like eggcreate at supermarket or something different? Please a little guidance here to uninformed.

thanks
Dave

[TippyToeX]

Dave, you would find eggcrate in the lighting department at most home improvement stores. Pic below. :) You might do a search here on RC in the photo gallery showing how some people cut it to fit the top of their tanks. Also, you will see it used as a tray to hold frags.

http://www.selectacoustic.com/images/eggcrate.jpg

[Jamesurq]

Also makes a nifty frozen food cube maker :)

[dmirza]

so to work best the eggcrate should be 3" away, even if using MH lighting?

Wouldn't that melt the eggcrate?

[gobygoby]

egggrate is pretty rigid plastic, doubtful it would melt. I would guess it would become brittle over time and begin to crack/fall apart.

Goby

[Jordan55]

Egg crate is also used in many buildings. If you look up at the lights... a lot of time the egg crate is right below the lights.... and think.. those lights are on very long and on everyday.

The lighting section is where you will find egg crate in a store.... I know I had trouble explaing what it was to an employee.

[H20ENG]

I like the idea of the "ensquaring" of the tank. That way you get less light spill from the sides, but dont lose your intensity directly below the fixture.
Eggcrate is made of styrene. I cannot remember the softening temperature of it, though, sorry.

I never took the original statement to mean that the lights put out 25% more power. The eggcrate obviously only helps focus the light that gets reflected back.
Thanks for the links, James!

[Steven Pro]

I made a concerted effort today when I was going around for work to look at the eggcrate fixtures I saw. Everyone I saw had the thick side pointing up. This is opposite of what Dana Riddle encouraged. In this manner, it did seem to block some of the light and diffuse the rest. But, with the thin side up, it would block very little of the light and focus it all straight down.

[superedge88]

I have the thick side up, is this wrong?!!

[Steven Pro]

Originally posted by superedge88
I have the thick side up, is this wrong?!! Yes, that blocks some light and disperses the rest. What you want to do is 'capture' the light and focus it downward into the aquarium. To do this, point the thin side up.

[johns]

Yes, that blocks some light and disperses the rest. What you want to do is 'capture' the light and focus it downward into the aquarium. To do this, point the thin side up.

Is there a difference you could actually see easily?? Or do you think it could only be measured with a meter?

Because I have been using eggcrate over my tank for quite a while just to keep fish from jumping out. It's cut into 2 pieces, separated at the center brace. I never even realized there were 2 sides to eggcrate until I read this thread. So last night I check and see that I have one piece on wih thin side up and 1 side on with thin side down (they HAVE always been used in the same orientation, because certain sections cut-out for equipment necessitate in which direction the eggcrate can be placed on).

I have never noticed any difference with the light on the 2 sides , and I tried last night turning them around (even though they dont fit perfectly) and still dont see a difference there either.

[Steven Pro]

To make a significant difference, the eggcrate must be within several inches of the light source. By placing is on top of the aquarium (to aid in keeping jumpers in the tank), the light that could have been directed into the aquarium has already been lost to the room. As such, it probably does not help or hurt much either way.

[johns]

My eyeball measurement yesterday is that the fixture is between 5 and 6 inches from the eggcrate.

BTW, it is a SLS Maristar, 250w HQI, supported over the tank using leg brackets (no canopy).

[coralnut99]

So is this the reflective eggcrate being used here, or the plain white?

Has anyone had any heat-related issues with the eggcrate? I would think that 5 inches below a 250W HQI, would soften it and make it bow. Another guess on my part is that if the reflective eggcrate is used, the heat could speed up the flaking of the reflective material.

[johns]

This is just the white eggcrate. Honestly, it does not even get warm to the touch. These same 2 pieces have been on my tank for over a year.

I believe the white relects away some of the heat. I posted in another thread about how the eggcrate keeps the tank a couple of degrees cooler. When I forget to put it back on after doing maintanence, I have noticed the tank temperature inching up a bit.

[coralnut99]

That's interesting as heck, I gotta say. I had eggcrate over my 120 to keep the Anthias in water. But when I upgraded to 250W HQI's the heat scared me. I thought it might soften and actually collapse into the tank while I wasn't home. Shows how paranoid I am. My paranoia did cost me 2 anthias. It would've been a third, if he hadn't jumped 2 feet right into my 125! Gotta give this a shot.

[johns]

As far as worrying about the stuff melting, dont give it a second thought.

I would just like to figure out these lighting intensity questions.

[alexinfla]

Wowza! I pop back out to check in and see my "simple little question" became a very interesting discussion....very nice talk guys, I'm learning a ton!

I too had been using my eggcrate (which I see Anthony calling eggrate...so it wont be the first time he taught me what things are actually called:) ) to simply keep jumpers in....now I know I can raise it, focus more light, and use another type of screening in a vertical manner to keep in the leapers.

Thanks~

[prugs]

It seems to me that if a tank runs cooler with the egg crate on. That you are reflecting energy away from the tank.

[alexinfla]

But I think energy=heat, and not always does light=heat. I mean, I've worked with a guy for a while now on reflectors using a type of metal that reflects light but transfers heat "up and away" from the water.

I'm wondering if the eggcrate with it's relatively thick plastic may actually be working as a type of small scall heat sink and keeping some of the heat from the tank.

Just thinking outloud with ya prugs.

Later~

[johns]

It seems to me that if a tank runs cooler with the egg crate on. That you are reflecting energy away from the tank.

I started wondering about the same thing this afternoon. I dont know if it makes sense to have a loss of heat and an increase in light at the same time. Unless somehow the heat can get reflected away more easily, whereas the light is being allowed through by bouncing from different 'angles'.

I dad say, however, that I thought there may have been a slight decrease in the light intensity when I put the eggcrate on (this is just subjective as I have no meter to measure it). The temperature observation is one I am more confident about. Maybe I should try this in a controlled way to be sure, but I seem to have seen the temp difference numerous times.

Also remember that the eggcrate is on in the wrong orientation on one side of my tank.

[Steven Pro]

If the eggcrate is sitting on top of the aquarium and not close to the light source, you are not going to get any of the focusing or increase in light that we have been talking about.

[johns]

I am 5 to 6 inches from the light source. I dont know if that is too far from the source or not?

[HowardW]

Would anyone know if it would make any difference in performance on what thickness eggcrate to use? Would the slightly thicker eggcrate create an even greater focus?

I've seen it offered in both 3/8" and 1/2" thick panels, and they all have the 1/2' square pattern which seems to be the standard.

[bsaastad]

Regarding heat vs. light -- this is right off the top of my head so feel free to confirm or deny as needed; I'm speculating, here. Isn't heat generated primarily from infrared light while the light our zooxanthallae needs is ultraviolet? Point being you can possibly absorb/dissipate heat from the infrared and still allow UV to pass, no?

[johns]

I doubt highly that something like eggcrate can differentiate between IR, UV, normal light while it's passing through. Whatever is happening is happening throughout the spectrum.

This thread is old and interesting that it's popped up again. But I'm sorry, I just highly doubt the eggcate I am using is doing anything to enhance the light passing through.

Again, I find it extrememly unlikely that that the obvious temp increase I see when the eggcrate come off means MORE light passes through. It has to be the opposite. Not to mention that I think I see a slight decrease in brightness. Bt that I cant quantitfy, because I dont have a PAR meter. I do have a thermometer.

[prugs]

ReeferAl has a PAR meter. He brought it to Rick Boyd's house for the Feb meeting. It had a submersible light pickup that allows you to get readings at various depths. I hope he will be able to make it to my house, when I hold a meeting.

[johns]

PAR meter would certainly answer this.

I'm already convinced however, that there is less light/heat in my tank with the eggcrate on. The only remaining question I have about this whole thing is the distance of the lights above the eggcrate. I asked a question a few posts up here about that, but still dont know the answer. My lights are low - about 5 or 6 inches from the eggcrate.

[prugs]

Personally I would not want to get much closer with MH. I have read before; that if you have PC's and they are more than 3" away from the water, they are just adding effect & not of any real light value.

Any of that purple milli ready to frag?

[dawgphish]

You say anything more than 2-3" off the water for fluorescents is a serious loss in intensity. I agree this is probably true, and have often wondered how much better my lighting would be if I could move it closer to the water.

[LBCBJ]

Anymore findings on this...anyone done some testing with a PAR meter?

[beachh]

i have a 90gal and i use 2 10k 175 watt mh and 2 4ft ho bulbs. i liened my canopy with tin foil and made tin foil shields over my mh and every thing been fine for years. Does anyone have any imput on this

[beachh]

i put a 2'' staghorn blue tip on the bottom of my tank and now its about 6'' from the surface. tank is 20'' deep. thay was about 15 months ago is this good growth for that coral, i have been taking frags of it too.