If you don’t have a lot of sensitive corals yet you can raise you alk to around 12 and that will help give your coralline a kick start. Once it’s growing well lower it back down to the range you want. Also make sure you have detectable nutrients in the tank, I can always tell when my nitrates or phosphates are low because the coralline doesn’t look as vibrant and stops growing
Raising Alk that high wouldn’t work for my system


