Your lighting is not sufficient.
Your SG is a bit low @ 1.023, I would strive for 1.026
You should have 0 ammonia, nitrite and close to 0 nitrate, alk should be 9-12 dkH, magnesium ~1300ppm.
HTH in perking those corals up, the red one looks like you dropped it a couple times and the skeleton cut through the flesh... ouch!... Should recover though.
It is not NECESSARY to feed them, since they are photosynthetic and all, but they will grow and recover faster if you do.
Your SG is a bit low @ 1.023, I would strive for 1.026
You should have 0 ammonia, nitrite and close to 0 nitrate, alk should be 9-12 dkH, magnesium ~1300ppm.
HTH in perking those corals up, the red one looks like you dropped it a couple times and the skeleton cut through the flesh... ouch!... Should recover though.
It is not NECESSARY to feed them, since they are photosynthetic and all, but they will grow and recover faster if you do.