Kessil lighting coral coloration

[Joey waid]

Two is not enough.. On that tank if it's long you need more. If it's tall you need more intensely......

 

[andys]

I ramp my Intensity to 65% and same with color

 

[njtiger aquariums]

Here my tank shot

 

[andys]

Here my tank shot

Very Nice. I love the shelfing

 

[willthethrill]

I ramp my Intensity to 65% and same with color

Mine are set exactly the same

 

[mcarroll]

My 120 is 48x24 footprint so I was told one 360we would be perfect for each 2ft x 2ft area

Assuming that means the wide lenses (140º per their site) then you want your lights about 4" from the water surface for optimum coverage and intensity.

That would give you approximately an 22" diameter of coverage at the water's surface from the center of the lamp. Intensity will double if you divide the distance to the water by half, so get out your lux meter and measure the before and after! I'm going from your avatar photo, but it looks like you could be close to double if you lowered yours.

Like this:

Here's more...
The 360 appears to be a 90 watt light – so while you may have "enough light" you don't have a lot of room to raise it up before the numbers drop too much. They drop by half every time he distance from the water doubles.

For perspective on power and area...
Adjusting for lens differences with your Kessils, my two tanks get an equivalent of about 120 watts on the low side and 200 watts on the high side. Those tanks are 36x12" and 36x18" tanks.

120-watts on the 36x12" (3 sq ft) tank only gives me 14,000 lux at the surface.

200 watts on the 36x18" (4.5 sq ft) give me a peak of about 50,000 lux.

Your tank has – at most – a similar amount of light coming from the fixtures, but you need it spread over an area that's almost twice the surface area of my biggest tank. (8 square feet.) Your tank is also deeper.

More Lux
Regardless of what you do with the fixtures, I suspect a lux meter would help a lot so that you could tell where the "better" lighting is and place the corals appropriately.

There are probably currently some zones that are too shady and some that are acceptable.

>14,000 lux usually all it takes to grow stony corals and as long as you do everything else well, they will be fine.
>20,000 lux usually makes for really happy corals that should be more hardy as well.
100,000 lux = 2,000 PAR = Direct Sun at sea level

A third 360 would definitely help even out shadowing some....but might not be "required".

See what you get for readings at 4" from the light.

 

[mcarroll]

Well I just downloaded the app. I don't have the t5s to compare anymore. I'm trying to figure out how to use the app though. Don't I have to hold the phone under the lights though

You should have to point the camera lens at the lights, roughly from the water's surface. Don't get the phone wet!

The app may have a setting to use the back camera or the from camera, so double check that if it doesn't seem to be working as expected.

 

[mcarroll]

Yea for those dimensions definitely more than 2 are needed

At 4" mounting height, @andys could get about a 20" diameter of coverage per fixture. (Assuming he hasn't There would still be plenty of overlap from three fixtures and intensity would be great.

But we can guess from the pics those lights are more like 10" from the water.

While that's handy for maintenance and probably aesthetically pleasing, it also reduces intensity by more than half, plus it makes the coverage diameter at the water's surface something like 50". So on a 20" wide tank, a lot of light is being "wasted" over the sides of the tank, which also lights up the room a nice shade of 20K. (This was me in the halide days!!!)

All these things converge to require more power/more fixtures.

There are secondary advantages aside from coverage and intensity to having more fixtures though, foremost that you will probably run all fixtures at a lower power, which should extend the life of your LED emitters.

@andys have you ever run your system closer to the water as described? Any thoughts? Have you considered using the Narrow 360 config at a higher mounting height? 17" of height seems like it would be optimal for those lenses. (Lenses are much better for changing mounting height than they are at compensating for spread issues.)

BTW, halides that were built like this (using DE bulbs, mostly) were most often run just a few inches above the water as well. If I'd had a suspension mounting for my old Coralife, I'd have removed the legs and run it even closer to the water.

2¢

 

[willthethrill]

You should have to point the camera lens at the lights, roughly from the water's surface. Don't get the phone wet!

The app may have a setting to use the back camera or the from camera, so double check that if it doesn't seem to be working as expected.

[emoji15]so my lights are at 9" from the water surface. Because my coast to coast overflow is a little wider than I'd like it to be, I had to reach out farther so the lights are centered over the rocks, as opposed to centered directly in the center, and I used those 90 degree adapters. So I couldn't drop the lights lower. I figured I could bump up the lights to higher power to make up for it if I saw that my coral weren't happy. But they are, just not vibrant colors as stated before. So at the current settings, at the water surface I'm reading 18k, then when I raise my phone to within 4 inches as you said, I'm reading 53k. Big difference.

 

[andys]

At 4" mounting height, @andys could get about a 20" diameter of coverage per fixture. (Assuming he hasn't There would still be plenty of overlap from three fixtures and intensity would be great.

But we can guess from the pics those lights are more like 10" from the water.

While that's handy for maintenance and probably aesthetically pleasing, it also reduces intensity by more than half, plus it makes the coverage diameter at the water's surface something like 50". So on a 20" wide tank, a lot of light is being "wasted" over the sides of the tank, which also lights up the room a nice shade of 20K. (This was me in the halide days!!!)

All these things converge to require more power/more fixtures.

There are secondary advantages aside from coverage and intensity to having more fixtures though, foremost that you will probably run all fixtures at a lower power, which should extend the life of your LED emitters.

@andys have you ever run your system closer to the water as described? Any thoughts? Have you considered using the Narrow 360 config at a higher mounting height? 17" of height seems like it would be optimal for those lenses. (Lenses are much better for changing mounting height than they are at compensating for spread issues.)

BTW, halides that were built like this (using DE bulbs, mostly) were most often run just a few inches above the water as well. If I'd had a suspension mounting for my old Coralife, I'd have removed the legs and run it even closer to the water.

2¢

My light height is 8 inches from the surface. If I was to raise then the light is spread beyond the foot print of the tank

 

[mcarroll]

at the water surface I'm reading 18k, then when I raise my phone to within 4 inches as you said, I'm reading 53k. Big difference.

Yeah!

So 18,000 lux isn't too terrible - the question is how much area in the tank get's 18,000 and how quickly does it drop below (e.g.) 15,000 lux and 10,000 lux.

You have to do it slowly if you've already got corals that are adapted to the light as is, but you have lots of room to turn the lights that you have up a few notches. Probably to 100% if you don't mind running them that hard. (May be perfectly fine to do so.)

You can expect more light to improve things, but it may take a few months and you may find out there are other non-lighting improvements needed before you get there.

 

[mcarroll]

My light height is 8 inches from the surface. If I was to raise then the light is spread beyond the foot print of the tank

Lights emit a continuous gradient of light out to zero lux/infinity and my diagrams are obviously finite, so you have to allow for some difference with reality in your imagination. But if you lower your lights to 4" (a little lower than 4", actually) you should be able to contain all of the useful light within the tank.

At 8" there's a significant amount of light "going overboard" so to speak...lighting up the room....a 140º lens covers a 44" diameter at 8"!

Here's more math, for what it's worth:

You tank is 8 square feet. The light at 10" covers over 100 square feet.

Assuming you're covering as much of the tank with each light as possible (not your goal, I know....just theory here) you're losing roughly (100 - 8) + (100 - 8) = 184 square feet of the potential coverage area.

   70º
    |\
10" | \
    |  \
90º -----
     22"

(Granted that gradient I mentioned is involved, so it's not nearly as simple as that.)

If you move the lights to 4", then it's more like this:

   70º
   |\
4" | \
   |  \
90º-----
    11"

...and practically 100% of the light goes into the tank.

This boost goes to direct irradiance by way of the 50% reduction in mounting height, but also gives a significant boost to internal reflection. Not to mention your living space losing that 20K glow! ​

 

[andys]

Lights emit a continuous gradient of light out to zero lux/infinity and my diagrams are obviously finite, so you have to allow for some difference with reality in your imagination. But if you lower your lights to 4" (a little lower than 4", actually) you should be able to contain all of the useful light within the tank.

At 8" there's a significant amount of light "going overboard" so to speak...lighting up the room....a 140º lens covers a 44" diameter at 8"!

Here's more math, for what it's worth:

You tank is 8 square feet. The light at 10" covers over 100 square feet.

Assuming you're covering as much of the tank with each light as possible (not your goal, I know....just theory here) you're losing roughly (100 - 8) + (100 - 8) = 184 square feet of the potential coverage area.

   70º
    |\
10" | \
    |  \
90º -----
     22"

(Granted that gradient I mentioned is involved, so it's not nearly as simple as that.)

If you move the lights to 4", then it's more like this:

   70º
   |\
4" | \
   |  \
90º-----
    11"

...and practically 100% of the light goes into the tank.

This boost goes to direct irradiance by way of the 50% reduction in mounting height, but also gives a significant boost to internal reflection. Not to mention your living space losing that 20K glow! ​

I would completely agree with the above statement. BUT from my couch it looks funny. plus the more important factor here the wife likes that height. Now you got me thinking of maybe i could do 6 inches. But again it works right now stuff grows why change it ?

 

[mcarroll]

Switch lenses (can you do that?) and just go up a few more inches with the mounting instead of down a few inches.

As far as the argument for changing it when the corals are happy? ...minor....removing the 20K light from the room might be the most compelling reason at this moment.

 

[andys]

Switch lenses (can you do that?) and just go up a few more inches with the mounting instead of down a few inches.

As far as the argument for changing it when the corals are happy? ...minor....removing the 20K light from the room might be the most compelling reason at this moment.

I don't think you can change the lens on these but i have no idea.

 

[mcarroll]

Hm...

They make an optical kit, but it sounds like it's only for the AP700...
http://www.kessil.com/aquarium/Accessories_opticalKit.php

If you were really interested, I think I'd call them about your light.

 

[willthethrill]

Looks like I gotta order the Kessil mounting arms and ditch the goosenecks. The mounting arms look like you can set the exact height you want and how far out too. With the goosenecks you're kind of limited to how much you can bend them.

 

[mcarroll]

Because my coast to coast overflow is a little wider than I'd like it to be, I had to reach out farther so the lights are centered over the rocks,

What are the dimensions of the two opening (front to back and side to side) at the top, excluding the drain box and tank trim?

(You really would like to not light the drain box if you can help it....not even the teeth. Save yourself one maintenance item permanently.)

If that drain box takes 6" and the trim is negligible, leaving the openings 24x18" each, then you might want the lights as low as 3".

Be prepared to experiment at any rate.

 

[willthethrill]

So I physically put the lights at 4 inches to the water to get a sense of how it would look and it looks odd. Almost makes me nervous. I did a search on a few forums to see what the consensus was with Kessil lighting heights, and about 90% of people say they have theirs 8"-10". I guess I'm gona try to bump up the lights from 65 to 75 or 80 and see if there's a change in coral coloration after a few weeks.

 

[mcarroll]

What lux are you going to keep them at now?