I would just get back to basics
1) water parameters
2) make sure you have 0 TDS water from R/O
3) lighting (intensity/schedule)
4) nutrient export (skimmer, W/C, etc)
5) good flow (to avoid detritus pooling up)
6) nutrient import (overfeeding fish/coral)
1.
PO4 1.4
NO3 20mg
3.
3x65 Jacod/Jebao AK-70 65W
2x36W Slim Led Aqua Marine
Schedule: 8h daily
4.
Skimmer: Tunze 9410
5.
Aqua Nova Wavemaker 13000, 40W, Qmax: 13000L/H
Aqua Nova Marine Pump 7000 N-RMC 55W
6.
They eat all within 30 sec of feeding