I'd say raise only the NITRATES and keeps phosphate low for coral growth SPECIALLY SPS and LPS. From my experience, I've always had nitrates at 75ppm or above as per Hanna and salifer test kit. And all corals look happy and healthy and colorful. NOW phosphate you can have them low and or high while nitrates are HIGH. I currently have my phos at 0.9ppm or above as per hanna and everything is striving. The only problem is High phos will slow coral growth, each time I reduce my phos to from 0.9 to .02 or .01 (my likings) and i'll start seeing the white tips and rim on the SPS specially my montis when I lower them. Downside to high phos is that any new acro will brown out if the phos is too high. But increase the nitrates slowly, why ? because if you increase or decrease phos or nitrates super fast, you'll end up with dinos or cyano.

I'll send you a pic or video if you wanna see....