Sufficient lighting for SPS?

[MT79]

My tank is a 29 gallon high, 18 inches deep. I am using 2- 75 watt VHO's, URI aquasun 10k, actinic 12k. Would this support SPS's?

 

[reefrunner69]

Would this support SPS's?

It would depend on the species. I think you would be OK with; Hydnophora, Stylophora, Pavona, Montipora and Pocillipora.

 

[captivereefs]

They may live and even grow but the colors may fade.

 

[brndfrb]

Can you do any sps or lps with a ustum ea life power compacts light. And i also have a 96 watt compact light also. So i have about 300 wats off light for a 65 gallon tank. Any kinds of those i can do?

 

[tyler]

Can you do any sps or lps with a ustum ea life power compacts light. And i also have a 96 watt compact light also. So i have about 300 wats off light for a 65 gallon tank. Any kinds of those i can do?

sps (monti should be fine) up top, lps in the middle, softies down below. 65 gallon is a pretty deep tank, so keep it like that and you should be fine.

 

[reefrunner69]

They may live and even grow but the colors may fade.

This is true of any lighting, I have had some SPS color up and some fade and I have a 175W Ushio 10K MH on a 20g tank

 

[captivereefs]

Actually 175 halides are a little under powered for most SPS to retain there color. 250's seem to be the minimum. We are talking mogul based bulbs not HQI. A 150 HQI buyb would also work. Tank size is irrelivant and so is the old watts per gallon ratio. If I put a 40 watt light bulb over a 3oz shot glass that is about 54 wats per gallon but it will not grow or keep coral alive. PAR and lumens are the deciding factors on a lights useable energy not just wattage.

 

[reefrunner69]

Actually 175 halides are a little under powered for most SPS to retain there color. 250's seem to be the minimum.

I'd like to see the documentation on this. 6500K Iwasakis provide more PAR than any other MH bulb of the same wattage, it gives the best growth, but most corals will fade in color

 

[loganj]

Isn't the deciding factor on MH not tank size but tank depth? I would think a 175 over a 12" deep tank like Kevins would be bordering on overkill. You can figure that a lot of his corals are probably not much more than 6" under the water surface...seems like a lot of light to me.
I also wonder what kind of results you'd get running 6500k Iwasakis in conjunction with a 10k bulb? Color and growth? Dead piece of aragonite?

 

[captivereefs]

Depth is also a deciding factor but i took his tanks depth of 18" into consideration. Also most people put there halides about 8" from the water to have better access to the tank. That equals about 26" . The VHO' are closer to the water but I am not a VHO fan myself. The tend to get less intense in the middle as the bulb gets older. This is just my opinions and nothing is written in stone in this hobby. But 99% of the colorful SPS tanks you see all have Halides over 175 watts.

 

[astride13]

Just my opinion, based on a bit of logic...

If I put a 40 watt light bulb over a 3oz shot glass that is about 54 wats per gallon but it will not grow or keep coral alive.

Wouldn't that be closer to 850 wpg?

Anyway, I disagree with that statement. If you could get a 40 watt bulb small enough to directly light a shot glass (obviously impossible, but I am following your analogy), you could grow anything that could handle that intense of lighting. I think a lot depends on depth of the coral and the bulbs distance from the water. You could have a 400 watt MH 18 inches (because of the heat) that would give less than a 250 watt MH right up near the water. Also, if you had a 250 watt MH and your coral was 4 inches from the surface it would get more light than a 400 watt MH at 18 inches below the surface.

 

[captivereefs]

I guess my point was that Light output meausered by PAR and lumens dictates intensity and the ability to support photosynthesis. Not the body of water the light illuminates. Watts per gallon is useless. You could put a flashlight over a thimble of water and it still is only generating as much intensity as if it were over a 180g tank. It just looks brighter in the smaller body of water.