watts per gallon????????

heller792

New member
Can some one please give me the best watts per gallon for my new reef setup. I have looked all over the net and get different answers all the time. My tank is 39Lx21Dx27H inches. I only have soft corals in there at the moment and 1 Montipora and all is ok but I would like to keep a selection of Acropora. Currently my lighting is 1x150watt halide from my old tank and 2 power compacts for Blues.

As always guys, Thanks
 

silverwolf72

New member
With all the different lighting you really can't go by watts per gallon. For soft corals your prob good on what you have now maybe adding another 150W wouldn't a bad idea though
 

pledosophy

Active member
If you want to keep acro's throughout the upper half tank I would go with dual 250w's MH's with the atnic T5's for supplementation. If you want to keep the acro's lower, go with the 400w MH.

JMO
 

heller792

New member
when you say go with 400w, I was looking at a dual 250w. What I mean is do I need the 400w to light the bottom of the tank or would the 2 x 250 watt be better than the 400 as i will have 500w alltogether
 

DevilBoy

New member
what he meant is that the 400w bulb will penetrate deeper down into the tank. so if you want to keep your Acros low in the tank then you will need or consider the 400w bulb

But to answer your question, no you dont need a 400w bulb to light the bottom of a tank, the tank would just be a low light area for lower light corals.
 

victor_c3

Premium Member
Given that your tank is 39" long, I'd say that you would need more than one MH light regardless of the light's wattage. MH lights with their reflectors are usually only good for a 24" spread. Selection between 250 watt and 400 watt should be determined by the depth of the tank and not on how many watts per gallon you're shooting for. As far as depth goes, I don't what would be suitable for your 29" deep tank.

Look at the "tank of the month" winner and see what their tank depth is and what wattage of MH lights they are running. Base your decision between 250 or 400 watt off of that. Also take note of what corals they are keeping at what depth.

Lighting is incredible confusing and I've only been reading threads and articles about lighting for a year now and I'm finally starting to get it.

Personally if I had a tank your size I'd go with 2x 250 watt lighting with T5 supplementation. For the MH I'd run 14k Ushio bulbs with actinic bulbs in the T5 for extra blue coloration.
 

korova29

New member
victor hit the nail on the head, it's easier to find an established tank close to your dimensions with the types you're looking to keep and just copy that setup.

I did this with the 90g I'm setting up...

MH bulbs are a different story, alot to do with personal preference of what you want the display to look like, ie bluer, whiter etc. and desired growth rates you're looking for.
 

Freed

It's what it's
Watts per gallon is a poor way to judge what kind of lighting you need. You could have 6000 watts of power compact bulbs on your tank but wouldn't be able to keep any acros on the bottom of the tank as PCs don't penetrate that deep.
 

DevilBoy

New member
<a href=showthread.php?s=&postid=12843643#post12843643 target=_blank>Originally posted</a> by heller792
are 20k more blue than say 14k or is it the other way round?


20k are bluer then 14k
14k are bluer then 12k
12k are bluer then 10k

most 10ks you get a crisp white but some do have a yellow tint to them
 

snorvich

Team RC member
Team RC
It is a function of tank depth and the type of corals you wish to keep. If you are less than 24 inches deep you can pretty much keep anything with 250 W MH. It is a function of how much light can penetrate to this depth. That is why people measure light intensity at various depths.

The higher the spectrum designation, e.g. 20K, the bluer the bulb. In the ocean, light is lost in the order of red, orange, yellow, green, blue violet as you get deeper. So, bluer bulbs simulate deeper ocean depths, whiter bulbs simulate shallow coral depths. The closer to natural sunlight, the greater the growth (this is over generalizing).
 

heller792

New member
So what is a good kelvin to get the happy medium between growth and aesthetics. I think the bulb i have in my 150w is a Arcadia 14k

cheers peeps
 

zacharytrimble

New member
A 14 K is actually a great medium. There are even more kelvin ratings coming out now that we didn't use to see...like 13k, 15k... What I'm doing however, on my 125 upgrade, is using 3x150 watt bulbs on a 22" deep tank and making them 10ks which can look a little yellow although they're powerful in that k rating, so I'm supplementing with actinic t5's. I'm placing sps high in the tank, and hopefully it will work out well, because I really want to stay away from a high electric bill, and still have good, sustained, slow growth of my corals. That's another thing to consider...many times people go with 400 watt bulbs because they want crazy growth...I just want health...and am willing to sacrifice a little bulb power for money savings.
 

heller792

New member
I am the same , I am happy to have slow sustained growth rather than fast and at least with the slow growth my calcium levels are maintained nicely usin a slow kalk drip rather than having to employ a calcium reactor and carbon dioxide, Oh the cost goes on and on. But seriously good luck with the new system zachary. Also I tend to keep soft corals at the bottom and i intend to keep stony corals at the top, I would be happy with this.
 

pledosophy

Active member
<a href=showthread.php?s=&postid=12843252#post12843252 target=_blank>Originally posted</a> by heller792
when you say go with 400w, I was looking at a dual 250w. What I mean is do I need the 400w to light the bottom of the tank or would the 2 x 250 watt be better than the 400 as i will have 500w alltogether

I meant go wityh dual 250's or dual 400's. Not one of either. ;)

In a tank that deep if you want to keep acro's on the bottom your going to need 400's. If you want to keep them in the upper middle portion a dual 250 will do.

So for the confusion. My bad.

From the sounds of your plans go wit dual 250's.

I use 14K myself in a few tanks withoug atnic supplementation. Am happy with it. Have changed just about everything else about the tank, but the lights are great. :lol:

JMO
 

hahnmeister

In Memoriam
<a href=showthread.php?s=&postid=12843252#post12843252 target=_blank>Originally posted</a> by heller792
when you say go with 400w, I was looking at a dual 250w. What I mean is do I need the 400w to light the bottom of the tank or would the 2 x 250 watt be better than the 400 as i will have 500w alltogether

In general, depends on the bulb you plan to go with, K rating, starter/ballast type, etc. All things being equal, dual 250's will be more intense than a single 400, and penetrate deeper. They will take up more space in the hood though. As it turns out, there are some 400 watt HQIs (need HQI ballast though) that really cook... the Aquaconnect 14,000K and the Ushio/BLV/Giesemann 400 watt bulbs like the 14,000/14,500K. Monster outputs that have double the output of a 250 of the same spectrum. But most 400's (probe start) are not as efficient as the 250 watt DE's or HQI, so they tend to not be worth it.

<a href=showthread.php?s=&postid=12843419#post12843419 target=_blank>Originally posted</a> by DevilBoy
what he meant is that the 400w bulb will penetrate deeper down into the tank.

I hope you just mean in comparison to a single 250... right?

<a href=showthread.php?s=&postid=12843663#post12843663 target=_blank>Originally posted</a> by Freed
Watts per gallon is a poor way to judge what kind of lighting you need. You could have 6000 watts of power compact bulbs on your tank but wouldn't be able to keep any acros on the bottom of the tank as PCs don't penetrate that deep.

Actually, PC's penetrate just fine, better than halides. Its just that they start out with such a lower intensity to begin with. But they are able to carry what they do make further down into the tank. The more spread out light field of equal intensity will go further than the one that is more concentrated.
 

dcombs44

New member
I'm not contradicting Hahmeister, and his occupation is probably enough to totally trump my thoughts, but I've honestly not heard anything that backs any of your statements. As far as standard bulbs and ballasts go, your basic MH are going to be more intense and penetrate farther than a standard PC bulb, and IMO a 400 watt bulb will penetrate deeper than even dual 250s in the area directly below the bulb. I guess I don't get the reasoning behind what you said. Granted, I'm no expert, and it appears that you may be, but again, I've just never read much that would agree with your statements. Sorry, I just want more clarification, because what i've read/heard/etc. backs what everybody else has told heller.
 

Slakker

Premium Member
+1 on that dcombs, but for different reasons ;) I don't buy into the "this penetrates better than that" argument.

As far as I know, a photon of light is a photon of light, no matter what produced it, and all are equally subjected to the same levels of attenuation at depth.

The different lighting options produce light at different spectrums and intensity, and with varying degrees of efficiency, but to the best of my knowledge none actually "penetrates" the water any farther than the others.
 
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