Acans showing skeleton

[SilverBulletPRN]

So I had these guys for over a year and they been growing the entire time but now they're starting to recede and show skeleton. Any idea why this might be happening? Other LPS are thriving all the acans are showing skeleton.

The only major change I can think of is the lights, it probably went from 160ish PAR to 220 over the span of one month.

Also dropped Nitrates from 20 to 10 and phosphates from 0.2 to 0.05 over 2 months

SG - 35ppm
Nitrates - 10ish
Phosphate 0.03-0.06
Mag 1380
CA 400
Alk 8.6
Temp 78

 

[SilverBulletPRN]

 

[MERKEY]

If you are sure no pests and no swings in other parameters other than lowering p04 and n03, I would say that the lowering of nutrients and the raise in PAR has hurt them.

What I've noticed with my torches and other lps is that the higher the nutrients the higher the PAR they can take.

But when you lower nutrients and raise par the corals get cooked per se.

 

[MERKEY]

There seems to be a balance that is different in every tank.

The sweet spot for my torches is p04 .05-.1 n03 10-20 and par 150-250

I have a few torches that like 300+ par but they come from tanks that run higher pars and have been living it in for years.

 

[SilverBulletPRN]

If you are sure no pests and no swings in other parameters other than lowering p04 and n03, I would say that the lowering of nutrients and the raise in PAR has hurt them.

What I've noticed with my torches and other lps is that the higher the nutrients the higher the PAR they can take.

But when you lower nutrients and raise par the corals get cooked per se.

That does seem to correlate. My acans were throwing some wild colors when nutrition was higher, same with the torches. Now they seem to be more bleached. I'm trying to strike that balance of a mixed reef as I'm SPS dominant right now. What parameters would you recommend?