Montis can take quite a bit of light in my experience. What are your magnesium and potassium levels? If those are low montis tend not to do as well.Monti digi all hate me . And plates for tat matter two . Encrusting I have a little better luck. However there is a small peace of purple plating monti that is growing. It’s actually my favorite plateing montie so cool !
i bought a green digi that almost died and has brown out . But it’s recovering. I think my lights are to strong ( halides ) because acropora do ok for me.