Acro base shading/lighting

[Boxofpurplerocks]

Hello everybody,

New to this forum, and also new to SPS, so bare with me. Just picked up my first SPS frag, a green slimer Acro. I'm told these are very hardy so I Figured this would be a good starting point.

After doing my due diligence on SPS husbandry practices, I feel I have a solid grip on what I need to do to keep this guy alive. Some background on my current setup: Biocube 32 that I've been running for just over 2 years. I have the hood removed, currently running a 165 watt mars aqua black box, 65% blues, whites set to minimum. Additionally running a Reef octopus classic 100 hang on back protein skimmer, avast marine pressure switch ato, and dosing saturated kalk solution via a 1.1 ml/min brs dosin pump hooked up to a timer.

Now, onto my question! I mounted my new slimer top and center in my tank yesterday, and he looks plenty happy in his current spot, plenty of par and high flow (dont mind the gsp I'll be ripping it off and moving it). However today I noticed that most of the front of the base is shaded by the top branches (Attached are pictures of the front and side, sorry about the quality). Is this a concern? Will the shaded portion of the base bleach or STN, and if so, how do I fix this? It seems like no matter which way I mount it, one side of this guy will be shaded. I'm sure this is just a silly question, but being new to SPS I really dont know what's okay and what's not. Any input is appreciated. Thanks!

 

[Ron Reefman]

Many corals do this, even in the wild. The shaded side will fade some and may even die in extreme circumstances (way worse than yours). I had a tri-colored birdsnest that grew to 12" tall, but only the top 3" or 4" were alive and even the bottom 1' was less colorful. The bottom 8" was just all white skeleton but the top 'mushroomed' out to be 4 times wider that the 'trunk'.

It's one of the few drawbacks to led fixtures in general. It's why a lot of reefers have added t5 fluorescent tubes to their led fixture. I tried that and hated the resulting lack of control (you can't dim t5's). It's a bigger problem with spotlight fixtures or even puck leds unless you have multiple sources (more than one fixture). It's a bit less of an issue with fixtures that do an array of leds spread out like the black box fixtures. A few fixtures spread them out even better than the black boxes do.

I solved the problem in my tank like this. My Photon V2+ got moved forward of the center line of the tank. Then I got an inexpensive all blue and white only fixture that looks a lot like the Photon and set it behind the center line of the tank. I also wanted to run just the blue leds in the back fixture. I stocked my tank with zoas and RFA's that fluoresce well under all blue leds so the extra blue made for even better fluorescing during the day when the Photon has 35% whites running. It also went a long way to reducing shadow issues like you are having.

 

[PatW]

I have LED fixtures also. The shaded side of SPS corals tends to be less than vigorous or just die off. My experience is pretty much like Ron’s.

 

[Boxofpurplerocks]

Ah okay, thanks for the input. So I take it then that anything short of changing my lighting, theres not much I can do? I guess no matter which way i position it there'll always be one side shaded.

 

[Ron Reefman]

Maybe consider; not changing your lighting, but adding to your lighting. Subtle difference but you don't necessarily need to replace your current fixture. And the additional fixture could be cheap. A single bulb t5 fixture doesn't cost much.

 

[MrObscura]

There's always going to be shading regardless of lighting used. Even the sun.

If the coral is otherwise getting proper light, flow, and nutrition it will be fine.

 

[Boxofpurplerocks]

Maybe consider; not changing your lighting, but adding to your lighting. Subtle difference but you don't necessarily need to replace your current fixture. And the additional fixture could be cheap. A single bulb t5 fixture doesn't cost much.

I definitely wouldn't be adverse to this. Do you have any single bulb t5 supplemental lights youd recommend? I'd be looking at about 22" wide max

 

[MrObscura]

While t5s can help with coverage in a large tank that isnt fully blanketed by Leds, theyre not going to do much if the tank is already getting good coverage.

The underside corals being shaded is unavoidable, it's just physics. Unless you can somehow shine light up from underneath them.

 

[Ron Reefman]

While t5s can help with coverage in a large tank that isnt fully blanketed by Leds, theyre not going to do much if the tank is already getting good coverage.

The underside corals being shaded is unavoidable, it's just physics. Unless you can somehow shine light up from underneath them.

I'm going to disagree with your last comment, at least a little bit. MH and t5 lights with reflectors do spread light around better than leds which, more or less just shine light straight down from above. A t5 bulb set at the front of my tank made a huge difference in shading and shadows under rocks and overhanging corals. But I didn't like the lack of color control or intensity.

 

[MrObscura]

Like I said, in a larger tank not getting full coverage from leds, I can see how it could help. Though to few t5s would lack coverage as well.

I think more leds, raised higher and/or angled as needed could accomplish the same thing. Though cost more than suplimenting with t5. Personally I don't get the hybrid approach. Maybe I'm missing something, but why not just go all t5?

Anyway, neither approach can work miracles and light from underneath. Youre still going to have shade on undersides. That's why some corals evolved to take a plating/tabling form, so subject as much surface area on top to the sun.