Frag dying around edges

[Acrofiend]

Hi everyone I’ve had this issue before and could never find the cause. All other sps have polyps out and are growing but I occasionally have this issue. What would cause this die off on the edges?
I feed frozen 1x and pellets 3x a day. I don’t skim but run a skimmer and occasionally dose aminos.
Alk: 8.3
Cal: 450
Mag:1420
Nitrate: 15-20
Po4: .09

 

[T-J]

Could be flow, lights or something picking at it?
How long has it been in your tank?

 

[Acrofiend]

Could be flow, lights or something picking at it?
How long has it been in your tank?

Almost a month now. I’m leaning towards lighting.

 

[T-J]

I'd check with a local reef club to see if you can get your hands on a par meter. Get a good map of your tank and adjust your lights as needed.
FYI, I have a light-colored acro in my tank (Northern Lights Tenuis) in about 230 par.

 

[Acrofiend]

I'd check with a local reef club to see if you can get your hands on a par meter. Get a good map of your tank and adjust your lights as needed.
FYI, I have a light-colored acro in my tank (Northern Lights Tenuis) in about 230 par.

Yeah that’s most likely what it is. Thanks for the replies.