How much lighting is too much?

[fishdude]

Happy New Year

My first question of the year.

I have a 120 gallon reef tank (and I'm green at this) that I have been running on a 20 000k metal halide and a strip 10000K just to add some yellow back.
I have no hard corals but a Maxima (blue? speceis) that require lots of light.
Is that enough light to grow hard corals? I have another 250 metal halide system now that I can hook up somewhere. So my question is.
Are two 250 watt mth bulbs too much or can I get by with what I have?
if I get the total 500 watts (I'll take out the strip) wil I have to but my bubble corals and mushrooms on the bottom?
your opinions please.

FD

[Namscam]

there is never too much light I think...I believe it was doug that had like 250 w or was it 400 w on a 20 g tank and his corals are doin great.. so theres no such thing as too much light

[Canadian Man]

It's hard to have too much light. You just have to acclimate the corals you get to your lighting.

I have 4 halides over a 6 foot tank. Most people run 3 halides on a 6 foot tank to have one every 2 feet. so my set up is

400w 20k------250w 10k------400w 20k------250w 10k

Now keep in mind my tank is mostly all sps corals

[Bob I]

It's hard to have too much light. You just have to acclimate the corals you get to your lighting.

I have 4 halides over a 6 foot tank. Most people run 3 halides on a 6 foot tank to have one every 2 feet. so my set up is

400w 20k------250w 10k------400w 20k------250w 10k

Now keep in mind my tank is mostly all sps corals

I am curious, what is your light bill like :question: :biggrin:

[Canadian Man]

It's not too much Bob.
Elec and Water together is $200

For the nice coral's I keep I think it's worth it.
Oh and don't forget that's including a waterbill that has a "bob hated" RO/DI on it. :razz:

[fishdude]

time to instigate.

When I'm at Wias I notice under his front window display he has a very bright lighting system and some of the corals (over the years) were not too happy.
Also in my travels I have noticed that my "candel light" coral would open up more when it was lower.

and also. I had a clam about half wat up the tank. was a brown type clam. that took hold,did well for 4 weeks ans then decided to uproot itself and go to the bottom of the tank. This clam was atatched to the rock I put it on originally; I tested it. But he went tp the bottom where he likes it. Oh and took a few steps alond the way.


So back to my original question.

How do you know when your corals complain.

I squint when there too much light.
you?


salute to all the fish/invert lovers

FD

[Canadian Man]

Well if they don't expand, grow or extend their polyps for a few month's then I figure their not happy.

It they bleach or RTN then I guess their not happy.

My light's are by no way too bright to make you have to squint.
Just bright enough so I don't ever have to turn on any light's in the basement. :razz:

[MitchM]

FWIW, you can provide your corals with too much light.

Read the section starting on pg 326 in Borneman's book Aquarium Corals, Selection, Husbandry and Natural History.

Pg 334 specifically mentions oxygen toxicity, caused by overlighting.

Also, I have the same lighting system that Wai's has, and I have seen corals in his tanks that were not doing so well either. Bleached, to be specific. I have bought some of those bleached corals and they have all come back to full color.
Remember that sometimes corals are in a dark box for extended periods of time during shipping. That can cause bleaching and other methods of coral death. (RTN, complications from sitting in their own waste and excretions)
Danny knows what he is doing when it comes to corals.

Mitch

[StirCrazy]

FWIW, you can provide your corals with too much light.

Read the section starting on pg 326 in Borneman's book Aquarium Corals, Selection, Husbandry and Natural History.

Pg 334 specifically mentions oxygen toxicity, caused by overlighting.

Also, I have the same lighting system that Wai's has, and I have seen corals in his tanks that were not doing so well either. Bleached, to be specific. I have bought some of those bleached corals and they have all come back to full color.
Remember that sometimes corals are in a dark box for extended periods of time during shipping. That can cause bleaching and other methods of coral death. (RTN, complications from sitting in their own waste and excretions)
Danny knows what he is doing when it comes to corals.

Mitch

did you read the new articke about lights and bleaching, they are now saying that if your coral bleaches from brighter lights it is due to a lack of current, and that you should increase the current when aclimating corals to brighter light to prevent bleaching.

I got to wondering if this is why I have never bleached a coral as I have lots of flow in my little tank, but who knows as when I put a new coral in I just plop it where it looks good and not worry about the light. except for the deep water acro I got.

Steve

[MitchM]

Which article?

Mitch

[MitchM]

...never mind..I just found it... :razz:

http://www.advancedaquarist.com/issues/jan2004/media.htm

Mitch

[MitchM]

So maybe it helps that the excess zooxanthallae (and it's byproducts) that's produced under extreme lighting is "massaged" out by strong water movement before it overproduces O2?

Cool. :cool:

Mitch

[Delphinus]

Some interesting points, I'm reading this thread thinking, hey, cool information. Then it occurs to me, hey, not really a club discussion but a general reefing discussion. SO ... uh ... mind if I move the thread? :razz: