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View Full Version : Light Intensity, 70MH or 96wPC


Bmgrocks
10/27/2007, 12:54 PM
Have a 10 Gallon with 96w PC, and wondering if I should purchase the 12 Gallon AP with 70w MH
(tank transfer)

Which lighting is currently better, would i be better off with the MH, I loose wattage.

PC wise i have some 9WPG
MH wise i have 5.4 WPG

Whats the difference between Light Intensity and Type, would i be better off with MH

everl0ng
10/27/2007, 02:26 PM
you would be much better off with the 70w mh imo. you would be able to house a more variety of corals, especially if you ever plan on sps or clams. and you'd gain an extra 2 gallons for tank stability, and you would be able to hide your equipment in the back chambers of the AP. also i believe marine depot and fosters and smith both have them on sale. let us know what you decide.

zack85
10/27/2007, 02:46 PM
no pc bulb can compare to even a 70w mh

mfp1016
10/27/2007, 02:47 PM
The MH will be much more intense. The only reason to select PC over MH is if you have heat issues, want to run actinic supplements (a phoenix 14k, or 20k bulb looks as good), or if you dont want to go open top. If you a smoker of any kind, the closed top is nice...

rickh
10/27/2007, 04:22 PM
Save your money--the number of lumens produced by both lights are approximately equal. The bulb selection for both lights is also very limited. R

mfp1016
10/27/2007, 05:06 PM
I firmly disagree, the lumens are not same. I've tested them myself with a lumen meter; unless I was testing bad bulbs....

everl0ng
10/27/2007, 05:10 PM
regardless, put the two fixtures next to each other and decide. if you know somebody that has the 70w MH take your 96w PC there and fire them both up and see which you like best and then decide whether it is worth it. in this hobby, a lot of it is based on compatability and stability, but when it comes to personal preference there is a lot of options out there.

MikePowell
10/27/2007, 06:31 PM
ahhh, another debate on which light is better.

phannay
10/27/2007, 07:46 PM
would the 150W sunpod be an overkill for the AP 12?

Rosseau
10/27/2007, 09:24 PM
<a href=showthread.php?s=&postid=11065706#post11065706 target=_blank>Originally posted</a> by phannay
would the 150W sunpod be an overkill for the AP 12?

No.

People are increasingly putting lights like this and higher over small tanks.

Though, it may be redundant if you're keep low light species only.

phannay
10/27/2007, 09:46 PM
<a href=showthread.php?s=&postid=11066230#post11066230 target=_blank>Originally posted</a> by Rosseau
No.

People are increasingly putting lights like this and higher over small tanks.

Though, it may be redundant if you're keep low light species only.

when you say higher, do you mean i can't use the stock mounting brackets? i have to raise it up higher?

sammy33
10/27/2007, 09:50 PM
It is tough to compare light intensities with watts. Lumens or PAR is a much better unit of measurement for light intensity.

Watts is simply a measure of power consumed. PAR (photosynthetic active radiation) is a measure of light produced or usable radiation. While I do not know the PAR on a 96w PC fixture I do know the PAR on a 70w Sunpod fixture and it is impressive!
http://samsreef.com/images/zoom/PAR/par-70w-7g.jpg

This was measured with a Apogee Quantum Meter calibrated to electric light sources. For comparison here is a 2 x 36w PC retrofit (72 watts) kit in a canopy on my FW planted tank.
http://samsreef.com/images/zoom/PAR/par-30g.jpg

You can see that as far as intensity just about the same wattage of light produces two different results. The metal halide fixture produces almost twice the intensity of the PC light.

Metal halide systems in general will produce more light per watt than most PC systems. :strooper:

Rosseau
10/27/2007, 09:55 PM
<a href=showthread.php?s=&postid=11066354#post11066354 target=_blank>Originally posted</a> by phannay
when you say higher, do you mean i can't use the stock mounting brackets? i have to raise it up higher?

I was referring to higher wattage bulbs.

Rosseau
10/27/2007, 10:03 PM
Nice demo sammy.

zma21
10/28/2007, 12:14 AM
MH > PC in EVERY case of intensity.

everl0ng
10/28/2007, 10:18 AM
i have my 150w sunpod ovr my 10g and i love it. i will be moving it to my BC29 when i get it though.

phannay
10/28/2007, 01:35 PM
<a href=showthread.php?s=&postid=11068228#post11068228 target=_blank>Originally posted</a> by everl0ng
i have my 150w sunpod ovr my 10g and i love it. i will be moving it to my BC29 when i get it though.

did you just use the stock mounting brackets? or did you have to raise it well above the surface of the tank

any heating/evaporation issues?

everl0ng
10/28/2007, 03:03 PM
i have the legs that it came with and i have it set over my tank resting on the mounting legs. sometimes it heats the tank up to 84 or 85, but now i keep a clip on fan running all the time and it keeps it at a steady 82-83 for me. it does cause more evap, especially with the fan now, so i just topoff a little more every day.

puckbs
10/28/2007, 03:27 PM
ha! i was just wondering this same question!! I have 96w pc powerquad (had it laying around) on a 20h. The original plan was to switch over to t5, but now you've got me thinking about the 70mh. wattage is power usage, does that mean the mh would use less electric than my pc fixture? Long island electric makes this a very important question...lol.

I really only plan on keeping zoas, rics, shrooms, and some other softies....

which would you go with?

jman77
10/28/2007, 03:49 PM
sammy33, is that the 14 bulb in the sunpod?

Bmgrocks
10/28/2007, 04:42 PM
Puckbs

It seems to me like the majority of RC is in favor of MH, rather than T5's or PC, mainly because I think they see it as tried and true, Eithor way, for what your keeping, zoo's palys, rics and softies, I think you would be fine eithor way. But i do have a biased, and would think that they would grow faster under the MH, and is more pleasing to the eye.

With Wattage meaning Power Usage being pointed out (duh now that i think about it) it would seem to me that the MH would use less electricity, but are u just powering the bulb, or are you powering the electronic ballast as well???

The sunpod does come with a stock 14k Bulb, nice hue, I see it as a true 14k, not a ultra white, not a intense blue like a pheonix...
Though the 14k on a Pheonix I think is the nicest 14k u can get.., a Pheonix looks/ feels more like a 17k...

jman77
10/28/2007, 04:46 PM
FYI: Pheonix's are really 20 + K bulbs with great par ! :)

m1enbo1
10/28/2007, 04:47 PM
once i went with metal halide, i will never go back to using PC's.

puckbs
10/28/2007, 04:47 PM
bmg...thanks for th input, much appreciated

InsaneClownFish
10/28/2007, 05:02 PM
Watts per gallon is a somewhat outdated and unscientific means of determining sufficient lighting for a reef.

To echo what most have said here, mh is your far better solution.

Here are two inexpensive options you might like:
http://phishybusiness.com/store/product_info.php?products_id=680
This is the solution I chose for my 16g custom nano. It's a new 150w HQI fixture from Current-USA that mates to their Solana system. It comes complete in brushed aluminum with hanging tree, has an external electronic ballast, and runs relatively cool. You can't beat the price either:
http://phishybusiness.com/store/product_info.php?products_id=791
http://img264.imageshack.us/img264/9657/img0493vd8.jpg

phenom5
10/28/2007, 05:09 PM
once i went with metal halide, i will never go back to using PC's.

exactly.

nietzsche
10/28/2007, 09:23 PM
get the metal halide! i had a 70w mh fixture over my 10 and everything thrived. for my biocube 14 i went with the 70w mh sunpod fixture. ill never go back to pc

phannay
10/28/2007, 10:31 PM
would a 70w sunpod be enough for keeping clams in a 12g?

Bmgrocks
10/28/2007, 11:32 PM
I would think so, the lighting in a MH penetrates much deeper than any pc light, if you are worried about light intensity, go with one of the less light intensive clams, like a dersa, and do supplemental feeding, which is usually required when the clam is under 2" anyways.

I Just ordered my AP 12 70HQI and it should be here within a week, from DFS, ready to see how it will turn out...

Unsure of what route to take, in my 10 it was bta anemone dominated, but a mixed reef, like my AP 24 allows a greater assortment of corals.

I'm planning on the same matinence schedual, weekly 20% waterchanges, the use of my AC 70 Modded Fuge, and will probably pick up dosing with the Kent Nano, 2 part supplement. (use in my 24 and love it.)

bboy aqua
10/28/2007, 11:52 PM
<a href=showthread.php?s=&postid=11072479#post11072479 target=_blank>Originally posted</a> by phannay
would a 70w sunpod be enough for keeping clams in a 12g?


i think it should be enough if u place the clam more in the upper section of your rockwork

i have a crocea in my 10g under the 70w sunpod fixture and i keep it near the top of my rockwork
so far its been doing fine and ive had it for about 4months

heres a pic of it

http://i34.photobucket.com/albums/d150/bboydrifta/mycrocea.jpg

phannay
10/28/2007, 11:56 PM
i like the look of clams in the sandbed though. the 150W should be perfect for that right?

bboy aqua
10/29/2007, 12:57 AM
the 150w should be enough
but for croceas and maximas keep an eye on them and if they need to be moved up then do so

puckbs
10/29/2007, 03:30 PM
just to reiterate.....

on a 20h,
i would be better off with a 70w mh than 96w pc or 96w t5?

Bmgrocks
10/29/2007, 03:33 PM
I honestly think, if you are able to afford MH go for it, pref a 150w, I think that 70w over a 20gallon tank may be too little to notice any significant differences over ur 96w PC, Anyone else like to comment.

There is a used 150w Sunpod in the used equip forum..

kydsexy
10/29/2007, 04:28 PM
ok so here's something i learned the other day. i went to my lfs and in his 33L with a 130W Power Compact I see a bunch of frogspawn. a few zoas, and of all things in the world a 2-inch clam! So I ask HOW? and he tells me that the sucess of clams depends on the amount of lumens reaching the depth to the water and not the wattage per gallon of water. So I think gonna put this to the test.

And on another note, before all rude or sarcastic comments come. I've worked with the store before and never realized that all of his small clams start out in this tank and are moved to higher lighting and larger tanks as the grow past 5 inches. He takes his fish very serious and just bought a 48" LED light for probably the most gorgeous tank I've ever seen! I'll post pics. The LFS is Aquarium Conservation in Cromwell, Ct. Stop in and chat with Jim sometime!

jeremyj0247
10/29/2007, 11:08 PM
what about the cost of running a MH. Is the difference in the electrical bill noticeable. I have heard MH's are a lot more expensive to run, but I am not sure I have never had one.

nauticac4
10/30/2007, 10:01 AM
I run 2 x 250 MH over my 120 and it adds about 35 bucks a month to the power bill.

Running a 70W or 150W would use 5-15 bucks of power a month depending on how many hours a day and what your utility company charges for power.

InsaneClownFish
10/30/2007, 11:14 AM
I think if I remember correctly, when I did the 150w HQI on the electrical calculator, I came up with $3.47 per month running 6 hours per day. I was afraid of the cost too, until I did a little more research and used a few of the electrical calculators with rates for the Northeast(very high). I was comparing this to an LED system that cost $850. My beautiful HQI pendant cost $206.95. The LED system running at closer to 8-10 hours a day would cost $1.77 a month. So yes, it costs almost double...lol...but it's $1.70 difference.

kydsexy
10/30/2007, 11:24 AM
i just noticed the par and lumens comparison on the other page and i was wondering if that person used the same type of light 6000K 10000k etc. will they be so drastically different?

puckbs
10/30/2007, 11:25 AM
in all fairness to that though, how long do the led fixtures last vs how many times do you need to replace the hqi at what cost per bulb?? STILL really tough to justify almost 1k on a light for a 20g tank...lol

Bmgrocks
10/31/2007, 11:10 AM
Im unsure of how long LED's last, but i kno it can be over a year and up, As far as when to replace an HQI, i would do so every 8 months or so...any input?

puckbs
10/31/2007, 02:22 PM
i think i had read that the led's last upwards of 8 yrs.....and i'm sure someone will have info saying otherwise..

m2434
10/31/2007, 05:53 PM
The PAR values provided seem a bit extream. Unfortunately I can't find any great comparisons. The best I could find is this.
Although written with planted tanks in mind, does provide some very good info.

Bulb comparison (http://www.aquabotanic.com/lightcompare.htm)

If anyone knows of a well controlled comparison I'd be intrested in seeing it.

Bmgrocks
10/31/2007, 06:43 PM
This was taken from Aqua Botanic Lighing, the link you provided and i found it intresting

"The most efficient bulbs in the sample are the metal halides, the high pressure sodium, and the tri-phosphors ADV850, Dulux, Pentron HO, and Aquarelle, about 20-30% more efficient than the average fluorescent. Of note is the comparison of bulbs with same spectrum but different power. The PC6700 with 55 Watt power is significantly less efficient than the 96 Watt version. This trend should be true for other fluorescent types as well, and also for the MH types. Interesting enough, a generic, traditional metal halide does not perform so well when put side by side with more evolved types such as the dense-line emitter MHs (MHN, Iwasaki65 and Optimarc)."

a few terms
MHN-Phillips dense line emitter MH 4100k CRI 80
ADV180-Phillips advantage Flourscent

quite a read....Give it a look

puckbs
10/31/2007, 06:56 PM
yeah, a WHOLE lot of words.....where were the pictures and diagrams???? lol

Bmgrocks
10/31/2007, 07:04 PM
yeah i wish there were, none....but it was intresting, it seems like in the fw hobby they condone the use of metal halide, and really push Power Compact, mainly due to the color spectrums offered. Unsure of when this was written, and assuming that they didn't use Marine MH, i can understand why, they are using the 3500k and 65k color spectrums, the amount of heat generated is one thing, but the Gross amount of yellow that is used probly turned them off to MH, the PC's offer a much whiter spectrum, and the Blues are useless in freshwater Aquaria.

Sounds to me like we need a SW comparison... as helpful as FW was..

m2434
10/31/2007, 10:02 PM
A VERY brief summary of my interpretation of the article, is that PAR/watt is best with MH's (out of the types typically used in a reef tank). High output fluorescents are potentially more efficient under certain circumstances, such as if driven by over sized ballasts and compact fluorescents are less efficient, but not by as much as suggested elsewhere (It is a good read, so don't take my word for these statments).

Of course, I'm still not sure PAR is really the best measure for reef tanks, as the measure was developed with green plants in mind. And would still like to see a well documented experiment with corals.... or at least with a really good light meter....

sammy33
10/31/2007, 10:37 PM
<a href=showthread.php?s=&postid=11069853#post11069853 target=_blank>Originally posted</a> by jman77
sammy33, is that the 14 bulb in the sunpod?

I used the Ushio 20K lamp in the PAR tests. The lamp (and ballast for that matter) was about a month old when I took the PAR readings. I also tested the current usa 14K 70w lamp that came with the sunpod fixture and the PAR was a bit lower only topping out at about 390PAR.

I never tested my 32w PC retrofit that I used on my mini bow 7. I should throw it back on there and see what the PAR is?

m2434
10/31/2007, 10:51 PM
Sammy33, your PAR values still seem way high, do you have more info on how your measuring...

Also, I found this thread, may be of intrest.

250MH PAR thread (http://archive.reefcentral.com/forums/showthread.php?s=&threadid=254667&perpage=25&pagenumber=1)

sammy33
11/01/2007, 08:13 PM
<a href=showthread.php?s=&postid=11093869#post11093869 target=_blank>Originally posted</a> by m2434
Sammy33, your PAR values still seem way high, do you have more info on how your measuring...

Also, I found this thread, may be of intrest.

250MH PAR thread (http://archive.reefcentral.com/forums/showthread.php?s=&threadid=254667&perpage=25&pagenumber=1)

Yes I have noticed that too. But there is not many other published readings (like mine) to compare to.

I have looked at that thread you linked and joe's measurements many times. I have also studiedSanjay Joshi's work on his site. (http://www.reeflightinginfo.arvixe.com/) I also reviewed the data from the bulb comparison link earlier in this thread. It seems that all of these PAR readings were done using a lab style setup to isolate the bulb/ballast performance (no reflector). This is usually a black box style setup with the light sensor mounted some distance from the bulb.

All of my PAR readings were done in situ. I literally stick the sensor in the aquarium and record the reading at that point in the aquarium. I have a 24" length of pvc pipe marked every 6" to hold the probe. The bottom of the pipe has an elbow to hold the probe in the correct position facing up. I try to take the readings directly under the reflector or as close to the center as I can get with the probe.

These readings simply show the PAR in that particular tank with that particular light setup. I am not using any conversions or compensations but just recording what the quantum meter reads on the probe at a certain depth in the tank.

m2434
11/01/2007, 09:08 PM
Good stuff - Thanks Sammy.

puckbs
11/03/2007, 02:56 PM
i decided to stop thinking about it so much...just put the sunpod 150w on my 20h and i LOVE it, obviously the intensity is much better, but so is the color...its crisper and i have the ripple effect in my tank, on my wall, and on my ceiling, i LOVE IT

AVALover5498
11/03/2007, 07:31 PM
Ok, just to clarify things for me and others. Can I put a 70 Watt MH over my 10 Gallon and succefully keep softies, lps, sps and clams?

-Chris-

puckbs
11/03/2007, 10:41 PM
I definitely think so

Bmgrocks
11/22/2007, 09:27 AM
are they making DE 70w Pheonix Bulbs, looking to replace the stock sunpod fixture

puckbs
11/22/2007, 09:58 AM
you know, i didn't really see what everyone was talking about with the color on the sunpod until now. I do like it, but it could use some more blue, and from what i hear phoenix is the way to go, i do no know about the 70w's though unfortunately

sammy33
11/22/2007, 12:50 PM
Brad - I do like the stock Current USA brand 14K lamp that comes with the 70w Sunpod. For me it was also not quite blue enough. I decided to try the 70w Ushio 20K and it was just about perfect. A good amount of blue but still balanced looking. The PAR is actually higher than the Current 14K lamp so it was a great upgrade.

puckbs
11/22/2007, 01:43 PM
good info sam, thanks...you don't normally expect the better par from the higher K