Gotcha. You'll primarily want to focus on ALK, CA, MG, PH. Nutrients is an entirely separate issue. SPS dominant tanks run at "low nutrients" usually by carbon dosing (there are various methods, but pellet reactors are a newer common method compared to vodka dosing). Controlling nutrients with carbon dosing, or GFO will prevent algae outbreaks, like cyano, dinos, hair, etc. You can add things like amino acids to your water column, such as Acro Power, which is intended specifically for SPS corals. In addition some folks like to spot feed their corals with high quality foods like LRS Reef Frenzy (among others).