one sided SPS color

[kevensquint]

I have a few frags of acro (stags) that look as when you go in a tanning machine with your arms pressed against your sides, and when you come out you lift you arms out to make a "T". They have nice color only on the parts that recieve direct light, the under sides are almost white. Since I only use MH, and no fluo. actinics, I thought this might be the trouble. My idea is that fluo. light goes everywhere and MH is a point source. What do you think? any similar experiences?

 

[Lowredranger]

i had the same problem but never figured out why except i figured that if my water quality was better they would color up but on some of my branching pieces the underside would loose its color.

 

[G-money]

I see that alot with stags - especially when they're wild caught, thick and receiving lots of light in my tank. I don't know if it's due to the increased diameter of the branches or what, but the undersides are almost always brown and the tops are nicely colored.

 

[manderx]

yup, i call them '2-tone' in my tank. i could take a small colony that looked well colored in my tank, and turn it 10 degrees and the whole thing turns brown. i've recently been through a move and some big changes so *everything* is brown all over in my tank at the moment.

i think it's root cause is water quality. light might seem to be the cause, because intense light forces color sometimes when water quality is good but not quite perfect, right where it hits straight on, by overworking the zoox so the coral has no choice but to reduce zoox denisty in that specific region. and alot of people like to say their water is 'perfect', but let's be honest. once you've seen a tank that's truely 'in the zone', you realize that even most TOTMs have good water, not always *perfect*.

i've had *brief* moments where i think my water was close to perfect i think (not trying to brag or imply my tank is anywhere close to totm quality). with no change in lighting the water quality magically improved (and probably accidentally since i am completely unable to maintain or reproduce it at will, which is why i can't brag). well, when the stars were aligned and everything came together the 2-tone went away, good color all round, in every nook and cranny no matter how i spun the coral around, even completely upside down. water quality was happy enough that the corals didn't need dense populations of zoox to provide enough sustenance, so it was able to broadcast the message to reduce zoox populations over the entire colony. i have a pic of this one coral in particular that went the same color as a glow-in-the-dark toy over every part of the colony, regardless of being shaded or not. that opalescent glowing minty green. never posted it because it looks like it's been beaten silly with photoshop. i'll see if i can dig it up (don't have my pics with me at work). what's odd is these bried windows of time seemed to usually happen right on the tail end of an algae outbreak (so the pics i do have of popping corals has them surrounding by nasty paradoxical algae). i think bad water quality made algae grow all over the rocks, then i was able to get the water quality fixed, and for a few days that remaining algae was able to suck down even more nutrients than normal to get things 'in the zone', then the algae faded away and the nutrients went back up to normal. so sort of an in-tank fuge even though i had an attached fuge with caulerpa and chaeto already. maybe one day i'll have it figured out...

 

[trueblackpercula]

great thread

 

[Redfish]

You don't need sunscreen in the shade.

The more dense the colony, the less interior color, generally speaking.

 

[kevensquint]

Well, the frags in question are not dense at all, they are small 6" tall pieces with only a few branches. Litteraly the branches are half colored (top half) and half white/bleached (bottom half). When I rotate the frag it takes 2 weeks - a month and the white side colors up and the color side bleaches. I was sure that it was because of the position of my lights are above the tank and the fact that I use only point-source (MH) and no fluos. suppliment.

 

[calvinreef]

I thought that happen all the time? the part facing light normally better color than the shaded area.

 

[Redfish]

Yep, thats the way it works. They always look better from the top.

 

[manderx]

ok, found that pic i was looking for. this pic looks shopped, or taken with manual white balance under actinic only. it's not. it's taken under 250w DE 10K AB and blue+. it's so dark because i had to drop the camera exposure down really low otherwise it would overexpose this coral (like it is in the bottom right corner of the second pic).

honest, this coral was this color over the entire colony, no 2-toning (like it normally is). i could pick it up and turn it upside down and even the very bottom was this color. i had even just moved this coral up closer to the glass to get a better shot for this pic of it than from it's normal place, so any 2-tone would be quite evedent in it's new orientation. and it's not bleached or unhappy, the pink tips were new growth while it was in this state for ~2-3 weeks. god it's depressing looking through old pics and seeing how cool my tank used to be...well, this is why i think the 2-tone is from imperfect water quality, and bright lights can give color to the tops of it when the water is pretty good, but if you get it 'perfect' it goes away.

there's another pic of it in my gallery, shortly after the first pic was taken. showing it going back to it's normal drabber colors and losing it's pop as the zoox densities rose. exact same lighting.