Is shadowing inevitable with every light source?

[Scorpius]

I ask because I currently run three Kessil A360we's over a 36in tank and some of my Acropora have tissue loss in areas that are shaded. I figured three fixtures with the outer two angled inwards would be enough, I guess not.

Will T5 and MH shadow my Acropora over time as well?

I like the growth and color I get with Kessil, but the shadowing is killer. Literally. I don't know if another fixture would help or not. *sigh* it never ends lol.

 

[saltyfilmfolks]

if you have a light it causes shadows.

But the bigger the source is over an object the smaller the shadow becomes. This is because the angle of the light at the most extreme edges lights the object too . IE a flashlight over your head. now put another one at 45 degrees from your head. it lights at a different angle.
Now put your headd in a box. Keep the two flashlights in the same place. Now the light bounces off the glass and back at yet another angle.
now make the flash light huge and the source is gigantic. so it lights from a very wide angles. We call that "wrap" in photography.

so no, t5 shadows your head in a box less, esp if its closer to the box. A mh will depend on the size of the fixture and reflector and how close it is.

to reduce shadowing w a single point light, set it so the circle of light hits just the inside edges at the top of the tank(wall bounces). it helps. a little. letting the glass on the top get dirty helps more with wrap.

 

[ReefQueen]

I don't keep branching sps and I run LED, but a buddy of mine switched from LED to T5 and mentioned that the base of his corals have since colored back up. It's definitely worth looking into

 

[Scorpius]

I don't keep branching sps and I run LED, but a buddy of mine switched from LED to T5 and mentioned that the base of his corals have since colored back up. It's definitely worth looking into

My problem is implementing T5's with my Kessil's and keeping a clean look without blocking the view from above which is important to me.

 

[ReefQueen]

My problem is implementing T5's with my Kessil's and keeping a clean look without blocking the view from above which is important to me.

You could build a floating canopy and mount it all in there.

These are just a few nice ones I found with a quick Google search.

 

[saltyfilmfolks]

https://www.reef2reef.com/threads/well-that-escalated-quickly.283810/page-6

Lamp shade on an led pendant.

 

[Gator1970]

After a few years out of the hobby, I started up a tank using an led fixture - I have to say I'm not very impressed with sps growth - I'm going to give it a couple more months and if there's no improvement I'm going with T5 or MH/T5 combo. There IS a lot of shading with the leds - you get shading with MH too, but that's why you supplement with VHO or T5.

 

[saltyfilmfolks]

After a few years out of the hobby, I started up a tank using an led fixture - I have to say I'm not very impressed with sps growth - I'm going to give it a couple more months and if there's no improvement I'm going with T5 or MH/T5 combo. There IS a lot of shading with the leds - you get shading with MH too, but that's why you supplement with VHO or T5.

ya gotta crank the leds up.

 

[Gator1970]

ya gotta crank the leds up.

Yes - maybe your right - I've got the fixture set at 20k because that's the colour I like, but it means that I'm not getting the full punch of PAR since the whites are off. I used to run 2x10k ushio MH bulbs, and 4-20k VHO tubes.

 

[Scorpius]

ya gotta crank the leds up.

Been there an done that with these Kessil's. There is a very fine line between enough light and bleach city.

 

[saltyfilmfolks]

Been there an done that with these Kessil's. There is a very fine line between enough light and bleach city.

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Been there an done that with these Kessil's. There is a very fine line between enough light and bleach city.

alk and nutrients are key to increasing par. If you had started with a 250w MH you would have just matched both to that. I know of 2 tanks that run in the 2000 par range at the top corals . It has Nothing to do with a kessil..
that and the lfs prob is 100par or less in the frag tanks now a days(i take a meter), so light and chemistry acclimation is key. Fwiw a 150 MH(decent reflector and ballast) puts out 2 times as much par as a 360.

 

[saltyfilmfolks]

Yes - maybe your right - I've got the fixture set at 20k because that's the colour I like, but it means that I'm not getting the full punch of PAR since the whites are off. I used to run 2x10k ushio MH bulbs, and 4-20k VHO tubes.

the 10k ushio bulbs are par MONSTERS......

If you ever get a chance talk to the owner Bill here. Hes an old school MH guy who went led. He gets it. https://reefledlights.com/

 

[mcarroll]

I ask because I currently run three Kessil A360we's over a 36in tank and some of my Acropora have tissue loss in areas that are shaded. I figured three fixtures with the outer two angled inwards would be enough, I guess not.

Will T5 and MH shadow my Acropora over time as well?

I like the growth and color I get with Kessil, but the shadowing is killer. Literally. I don't know if another fixture would help or not. *sigh* it never ends lol.

What lights did you convert from? It sounds like you made a pretty big switch.

Angling your fixtures is going to cause a lot of light to bounce off the water vs penetrating into the water.

Can you post a pic of your light setup?

More fixtures will help but it's possible that zero would be even better – but I wanna hear the answer to the first question first.

Curious also about your water parameters, just for background info.

 

[mcarroll]

Been there an done that with these Kessil's. There is a very fine line between enough light and bleach city.

alk and nutrients are key to increasing par.

...and a light meter.

If you control your lighting changes using any kind of light meter, keeping them small and spaced out by at least a few weeks per change, your corals will have a chance to adjust. They will manage to adapt under most circumstances, but some extra nutrients in the water will help them adapt faster since they'll be doing a lot of tissue repair. You overwhelmed their shielding....so they'll be experiencing some tissue damage AND they'll be building new shielding.

As a rule of thumb I usually say to keep changes at/under 2000 lux.

If you're up for some reading, I have a ton of links to great articles on this very topic up on my blog in the Coral section. (Or browse just articles on Nutrients or just on Light.)

Some excellent articles to start with:

• Limited phosphorus availability is the Achilles heel of tropical reef corals in a warming ocean
• Results of the 1991 United States-Israel Workshop, “Nutrient Limitations in the Symbiotic Association between Zooxanthellae and Reef-building Corals”
• Is the coral-algae symbiosis really ‘mutually beneficial’ for the partners?

Maybe even just run a search on the blog for phosphates or nitrates.

 

[Scorpius]

I've been using Kessil A360we's since I started reefing in 2013.

I just put an order in for two T5 retrofit kits to add to my Kessil's. I bought the Hamilton Aruba V series. To add them to my existing lighting I bought the Kessil extension slider bar they make for the A-arm series to give me more length to mount my T5's.

The goal is to have my three A360we's down the middle and one T5 behind and in front of the Kessil's. I bought 24in T5 fixtures so I can suspend them in between the two outer Kessil Arms and then run the T5 power cords down the outside of the Kessil arm to neaten up my light monster. lol

This is overkill on lighting, but my plan is to start the T5's at only two hrs. per day and go from there as needed.

 

[mcarroll]

So wait, you run three wide-angle lights over a 36x18" tank?

Can you post a pic of your installation as-is?

 

[Scorpius]

So wait, you run three wide-angle lights over a 36x18" tank?

Can you post a pic of your installation as-is?

Yup, I know odd right? The two outer 360's are angled inwards, about 30 degrees, and the center one is pointed straight down.
There's a guy on Reef Central who has my exact same tank and Kessil's and he's now running Ap700 mounted inside a ATI Sunpower fixture. The shadowing the 360's series is unreal.

I can get a picture with my cell this evening.

 

[mcarroll]

Lights
Still wanna see the pic, but if the shadows bother you that much, it sounds like you simply need to switch to LED strips and forget the idea of using spotlights.

Check out GHL's Lightbar2 as well as Current's Orbit Marine Pro. (There are lots of brand options if you don't need it to come with a controller.)

Corals
The coral issues might still be unrelated to lights IMO....three wide-angle kessils "should" generate a brick-ton of reflected light in the tank, eliminating or reducing much of the shading issues so far as the corals are concerned.

Any other changes or "events" that the tank has had in the last six months or so that could coincide with the tissue loss you mentioned, like rearranging some or all of the tank? Anything.

Still curious about present and past test numbers too...minerals and nutrients.

 

[Scorpius]

Lights
Still wanna see the pic, but if the shadows bother you that much, it sounds like you simply need to switch to LED strips and forget the idea of using spotlights.

Check out GHL's Lightbar2 as well as Current's Orbit Marine Pro. (There are lots of brand options if you don't need it to come with a controller.)

Corals
The coral issues might still be unrelated to lights IMO....three wide-angle kessils "should" generate a brick-ton of reflected light in the tank, eliminating or reducing much of the shading issues so far as the corals are concerned.

Any other changes or "events" that the tank has had in the last six months or so that could coincide with the tissue loss you mentioned, like rearranging some or all of the tank? Anything.

Still curious about present and past test numbers too...minerals and nutrients.

Here's my test results as of 4/15/17
8.15 dkh

425 Ca

1410 Mg

.039ppm P04

0.5ppm Nitrate

1.027 Salinty

8.3-8.6 PH

380 Potassium

I am dosing Fluconazole for Bryopsis and I havent skimmed much in 4 weeks which I know is probably the trigger for the tissue loss I see, but the tissue loss is reversing on most of the ones that were losing tissue.

My issue with shadowing has been a long standing gripe with me and LED's. I'm just now starting to see some issues associated with it namely color loss and some tissue loss in the shaded areas.

I'm trying to head off any further issues with my Acropora and T5's should fit the bill for more fill in light and give my corals anything the Kessil's may lack.

It's all a grand experiment in this hobby.

 

[Scorpius]