Admittedly I have not been keeping up with this thread so please excuse if I say something already stated. Removing hair algae and expecting coralline to grow in its place might be a tad bit ambitious. Identifying the causes of the hair algae is where you should start – what coralline desires and when hair algae desires are radically different environments. Hair algae, check phosphates, nitrates, DOC’s, abnd old lighting. Coralline, proper lighting is very important, consistent SG, calcium around 400, ALK about 3.0, strontium, no nitrates or phosphates. So if you have hair algae you truly need to resolve the cause before you can have reasonable expectations of growing coralline. Again, I am at work and didn’t read all the posts – sorry if I repeated or missed an obvious. Good luck to you !!