teach me about polyp extension

[Nano]

As the title says.

So I have a few choice sps frags in my tank, and see little to no polyp extension they are mid to high in the water column, light peak at about 45% on my ai sol but the only frags exhibiting and PE are my birdsnests what can I do to change this? even my purple bonsai is slightly browned out with 0 PE on a regular basis. Any tips/tricks?

Thanks all

Oh and params
Nitrates less then 5ppm
0ppm ammonia
0ppm phos
440ca
Mag 1360
9alk
Salinity 1.0245ish