Distance vs. Duration

[ZZROCOOL]

Has anybody ever experimented in changing lighting variables that have nothing to do with the type of bulb?

Regardless of the bulb (color temp, wattage, etc.) you can change the distance from the water surface (intensity) or the duration (time). Has anybody do so and had significant difference in results? Let?s leave color temp and wattage out for now, also let?s assume we are working with MH bulbs. Lets also assume we are using SPS as a basis.

I am thinking about this for a few reasons the least of which being operating cost, but also heat, and of course looking for better coral color and growth.

 

[meschaefer]

Has anybody ever experimented in changing lighting variables that have nothing to do with the type of bulb?

Regardless of the bulb (color temp, wattage, etc.) you can change the distance from the water surface (intensity) or the duration (time). Has anybody do so and had significant difference in results? Let?s leave color temp and wattage out for now, also let?s assume we are working with MH bulbs. Lets also assume we are using SPS as a basis.

I am thinking about this for a few reasons the least of which being operating cost, but also heat, and of course looking for better coral color and growth.

I have been playing around with this as well, but don't have any data for you as I am to early into my experiment. I have a couple of frags in my tank at different levels, and am waiting to see if there is a big difference in growth, etc. etc.

 

[ZANYMASTER]

Weird how I can put some of my acros on the bottom with my T5's and get better color.

 

[ZZROCOOL]

hmm

Let me know what you find
only issue with frags at different levels is that the amount of water has a lot to do with the amount of intensity drop off. I am thinking about moving my lights closer to the water rather then move the coral.
I also am really interested in the duration and to see if increased intensity effects the necessity for having my MH on all day

 

[Wes]

i just cut mine down an hr to 7hrs/day to see if it deepens my color a bit.

 

[jhale]

less MH is better than more MH.

I know both Rich and Shaun have cut their photo periods way down, around 3 hours of MH, and the SPS did not suffer at all.

 

[Wes]

less MH is better than more MH.

I know both Rich and Shaun have cut their photo periods way down, around 3 hours of MH, and the SPS did not suffer at all.

i would hate to look at my tank under actinics only all the time...

 

[fritz]

Boogersworth.
I always wonder when I see on RC guys who are running dual 400s, 16" off the water for 4-6 hours a day. Why not run 250s closer to the water for a longer period of time?

 

[NYreefNoob]

not that i use mh on my sps tank but i did notice a significant difference in color in my sps with cutting from 8hr's a day to 6 and thinking of cutting back another hr or 2, tank also gets sunrise sun as the window it's next too is where the sun rise's

 

[Wes]

Boogersworth.
I always wonder when I see on RC guys who are running dual 400s, 16" off the water for 4-6 hours a day. Why not run 250s closer to the water for a longer period of time?

i remember a while back all of the barebottom mafia on RC was saying, "oh now that your water is so clear you are bleaching out your corals with too much light, blah blah blah". My theory is they were starving them.

 

[Cloud1921]

Good question ZZROCOOL.

I actually experimented with this idea on my old 90 gallon tank.
I ran 2x 250w xm 10k halides, with 2x t-5 actinic supplementaiton.
The tank was approximatley 1 1/2 yrs old and consisted of a mixture of sps, lps, and softies on a zeovit system.

Halides were originally operated at 10hrs daily.
I then went down to 7hrs and finally stayed at around 5hrs daily.
Growth appeared to be the same. Maybe I could have gone lower.
Duration was more of a con edison bill for me. :tongue1:

Heightwise, I experimented with my custom wood pendant at as low as 4" from the surface (just about right on top of the frame) to as high as two feet.

Do keep in mind, I usually leave it at a specified height for at least a week.

At low heights, it seemed to bleach corals regardless of duration. I did try 3 hrs daily for that. Temperature was DEFINETLY an issue at these heights.
There would be a ~+5 temp increase. The temperature issue was fixed with better vornado fans and central cooling.
My caps and zoas always seemed to wither away at these heights.

At heights closer to 24", there didn't seem be enough penetration for acros on the barebottom. I lost three small colonies that were placed on the barebottom. ( A crayola plana, stag, and hoeki)

The sweet spot was around 6" to 12".
There appeared to be good polyp extension and light coloration (Possibly from zeo's low nutrient system as well)
At the time, I remember setting 3 frags of acropora nana at three different levels; high, med, and low.

There was good growth in all three, but the top frag really grew and encrusted faster.

I didn't really plan on documenting the process.
I wish I had pictures to show, but I was never really the type of person to take pics of the tank.
The sad thing is that I lost almost everything during my tank upgrade.
However, those who have been over my house, when I had the 90 gal, can probably vouch for me.

90 gal tank specs
2x 250w XM 10k (Spyder reflectors, PFO ballast)
2x t-5 actinic supp.
Tunze 6100
Tunze 6000
MTC HSA-250.. Powered my GenPCX30
Quiet one 3000 pump
Two part B-ionic additions
Zeovit system

Boogersworth.
I always wonder when I see on RC guys who are running dual 400s, 16" off the water for 4-6 hours a day. Why not run 250s closer to the water for a longer period of time?

I was stuck in that dilemma as well.
On my current 140g tall tank (30" tall), I was concerned about 250 watters not being enough.

I was running 2x 250w xm 10k's on spyder reflectors.
Growth was alright, but was not sufficient at the lower depths.
I kept my lights at around 8" from the surface. Anycloser and I would have had melted acrylic lol :tongue1:.

At the moment, I am still running 250 watters, but in lumenarc reflectors.
Bulbs are 2x 10k reeflux on icecap ballasts.
Things seem to be just fine right now at 5hrs daily.

 

[tosiek]

Nik, Your taking into account feeding irregularities, weather affects, parameter deviations, salt used, documented water changes and amounts, tank temps during the day and everything else that goes into it as your doing these tests right?

Just making sure you cover all your bases. :chefico:

 

[ZZROCOOL]

Tony to some extent I am. I am just thinking about the lighting specifically.
For instance if you put 1 400 watt MH 6" from the take for 4 hours does that have the same effect as 1 400 watt MH 12" from the water for 8 hours? From a cost and heat perspective half the time at half the distance would be great! Which has a better effect on the coral color and growth. Assuming all other parameters are equal!

 

[JLAudio]

Obviously a concern is going to be burning the corals. I wonder if their is kind of an optimal point, where anything more will cause burning and anything less will be lower growth rate.

At least if your going to try this do an acclimation perios. When I swithched from 250 DE to 400 DE, my millipora showed some browning on the top tips that reached the top of the water I lowered it and its doing very well and that was at 3 inches below surface and light 10" above water.

But overall this is an interesting concept and if proven successful can be a very cost effective way to keep growth in SPS without electric bill being so high