I’ve noticed a few things, starting from dry rock to being able to grow SPS and acros. Firstly I feel that your lighting and flow needs to match, high light and high flow. Also your nutrients should be relative to your Alk. What that means is if you’re having trouble keeping your nutrients consistent but you’re running a higher alkalinity, acros will tend to grow skeleton faster than they can create tissue which will lead to burnt tips potentially and then subsequent algae growth, for example. What helped me get over the hump was correct placement in the tank, managing my Alk level to achieve great stability, boosting my pH from 7.8 to 8.3, and then lastly, I began dosing Brightwell Microbacter 7 daily, along with phytoplankton. Yes, acros do better in a mature system, but that’s usually because of a couple things: stability and bacteria. The bacterial strains that are present in successful, stable reef tanks are much different than new tanks. If you can seed some of those bacterial species into your tank and then maintain good, stable water chemistry, there’s no reason you can’t keep acros with proper lighting and flow.