Four T5 HO Bulbs on a 45 Gallon Frag Tank (12" Tall) Is this Low, Medium, High Light?

[that Fish Guy]

Four T5 HO Bulbs on a 45 Gallon Frag Tank (12" Tall) Is this Low, Medium, High Light?

I have Four Bulb T5 HO Fixture on a 45 Gallon Frag Tank (12" Tall).

I am worried about my new Acans getting too much Light Though (Most people say they like Low Light but I have heard some people say they like Medium Light).

The Light is a couple inches above the Tank (On Legs).

The Acans are about 1 Inch off the Bottom on Egg Crate.

They look awesome now.

Do you think that this will be an issue long term though?

Is this considered Low, Medium, or High Light?

 

[Dkuhlmann]

I would call it med to high, but should be fine once they are acclimated to it. Just remember to always start them on the sandbed. You can also make a rack to hang the lights by over your tank if you want to get it a bit higher.

 

[Mark9]

I think you're close with 4 T5 bulbs, definitely not too much light, maybe a tiny bit low.
4 39 watt 36" bulbs = 156
4 * 45 = 180
I'm using the old 4 watts per gallon.
I know people dismiss it, but for T5's it's a good baseline estimate.

 

[that Fish Guy]

I think you're close with 4 T5 bulbs, definitely not too much light, maybe a tiny bit low.
4 39 watt 36" bulbs = 156
4 * 45 = 180
I'm using the old 4 watts per gallon.
I know people dismiss it, but for T5's it's a good baseline estimate.

They are 54 Watts each so 216 Total.

So 4.8 Watts Per Gallon.

But the problem is most tanks are much taller than 12"

Once you pass 12" PAR plummets.

But even Corals on the bottom are above that.

So I am worried that they are getting Blasted with Light.

If I had a Tank that was Shorter and Taller like 20-24 Tall I would not be concerned.

I have no issues in my 55 but it is 21" Tall so I just put Low Light Corals on the Bottom.

I can't do that with this Tank.

 

[Mark9]

Ah, got it, i thought it was a standard 45 gallon size.
You may have too much light then in such a shallow tank.
Lift the fixture?
Remove a bulb?
Run 2 actinics instead of 1?
I think you have options.

I totally missed the 12" part, guilty as charged

 

[Reef Frog]

Light intensity vs coral placement is so subjective unless you have a meter. It's frustrating sometimes. Plus even if you have accurate PAR readings, it's not like the acans came with an owners manual.

But I think 4 T5 two inches off the waterline in a 12" deep tank is nearing the "high" range if the frags in question are in the middle (not off to the sides) of the tank. The potential for light shock & color loss is there IMO.

My 6 bulb T5 is about 2" off the water line in an 18" deep tank. This can be a little too much for some acans on the sand bed, but not all. But some acans do fine higher, but they are mounted on the vertical because the light isn't hitting them at 90 degrees. So it's very hard to say for sure what combination is best in a given circumstance.

But in your situation I would, at a minimum, acclimate new acans at the very end of the tank where light is weakest. Better yet, do the aclimation under a canopy of egg crate, maybe with a piece of screen fabric initially. Or any other semi shaded location.

To confuse things even more, I think this light intensity variable may be affected by nutrient levels, bulb color temperature, & maybe even a GFO/alkalinity level correlation. . It can seem like a moving target so only close observation & a willingness to make changes is the only way to know for sure.

All we know is color is lost & bleaching begins when the symbiotic dinoflagellates responsible for color begin to bail out because something in the local environment isn't right. And it seems improper lighting, usually too much, has to be on the top of the list.

 

[that Fish Guy]

Ah, got it, i thought it was a standard 45 gallon size.
You may have too much light then in such a shallow tank.
Lift the fixture?
Remove a bulb?
Run 2 actinics instead of 1?
I think you have options.

I totally missed the 12" part, guilty as charged

I cannot Raise the Fixture.

I have SPS in there so I do not want to take out any bulbs.

I use 4 ATI Blue Plus Bulbs.

 

[Mark9]

I cannot Raise the Fixture.

I have SPS in there so I do not want to take out any bulbs.

I use 4 ATI Blue Plus Bulbs.

Only blue+? Interesting.
I'm running 4 blue+, 1 coral+ and 1 actinic.

This is what ATI says about

Blue+
" Recommended as a supplement to metal halides or in combination with Aquablue Special, Purple Plus, or other full spectrum T5 bulbs."

Coral+
"Recommended Use: As a stand-alone bulb or in combination with Blue Plus, Purple Plus, True Actinic or other supplemental T5 bulbs."

 

[that Fish Guy]

Only blue+? Interesting.
I'm running 4 blue+, 1 coral+ and 1 actinic.

This is what ATI says about

Blue+
" Recommended as a supplement to metal halides or in combination with Aquablue Special, Purple Plus, or other full spectrum T5 bulbs."

Coral+
"Recommended Use: As a stand-alone bulb or in combination with Blue Plus, Purple Plus, True Actinic or other supplemental T5 bulbs."

Yes, only Blue Plus.

I don't care what ATI says.

They are stuck in the past.

Things evolve, especially in this Hobby.

Acans do Best under Blue Lights (Specifically T5).

And I cannot stand White Light since it makes Corals look Ugly.

All my Tanks are Blue, Blue, and more Blue.