SPS tips bleaching?

[ReefsandGeeks]

I had a question about SPS bleaching. I'm new to reefing and have a half dozen coral frags in a 40 gallon with a 160 watt LED light, one of which is a green birds nest SPS. I've been slowly adding a couple percent power with the light almost every day slowly acclimating the coral to the light. currently, I'm about 60% of full power after about a month. Last night I was looking at my birdsnest in the actinic light and noticed that the polyps at the tips of the branches were very pale compaired to the bright green of the rest of the polyps. I tried taking a picture, but without a flash you can't tell, and with a flash the coral looks fine. So I don't have a picture to post with it.

When SPS has tip bleaching, is it the hard skeleton base that bleaches,the polyps. or both? I'll look closely when I get home at the skeleton to see how it looks in normal light, but i haven't noticed anything out of the ordinary with it. Just the polyps under the actinic light. Maybe this is new growth starting? I haven't noticed any growth out of it yet, but my other soft corals and hammer frag are growing. One red zoa frag went from 3-6 polyps since I got the frags(all at the same time). Please let me know if I should be worried about the pale polype color or not, and if so should I back off on the lighting slightly and keep it there? I don't have a PAR meter so I've just been keeping a very watchful eye on my coral daily and making very small adjustments in light so I can catch any negative effects.

Water perameters are
Ammonia:0
Nitrite:0
Nitrate: ~3-5ppm
pH: 8.0-8.1
KH typicaly 8-9 but haven't checked in about a week or two.

I drip kalk at low saturation as my top off, and base it's consentration off of my KH so it stays steady at 8-9.

[ReefsandGeeks]

Nobody know if SPS tip bleaching is refering to the polyps themselves or the skeleton structure? If it is bleaching how can I mitigate the problem before it gets bad?

[SPS_Addiction]

white tips vs burnt tips?
burnt looks like tips are dying and, well, burnt. usually caused by low nutrient system and alk higher than 8-9.
new growth will appear white, but that is easy to figure out because coral getting bigger in size.
bleaching reffers to polyps and body of SPS turning white.
Also check tissue, if tissue dying, then it's Rapid Tissue Necrosis.

[burkhart.5150]

Pictures?

[ReefsandGeeks]

Thank you SPS addiction, I will take a close look at it when i get home today. As far as i could tell last night, it was just the polyps on the tips that were white, or almost white, not the body. It's probably growth, but I didn't think the new growth would be a different color. New to coral though, so everything's new basicaly.

[ReefsandGeeks]

I'll try to get a better picture tonight. I took some last night, but my phone picture I took with only actinic lights on you couldn't tell the polyps were a diferent color, same thing with the flash on. Might be able to play with lighting or phone settings to get a better picture