IMHO, I agree with everyone who is saying that you need to test your param's, at least when there are issues. I used to test daily, then weekly. My tank has been so stable for so long that I only test every other week now. However, as you requested a "tip", I have xenias and zoas that didn't grow much. I began adding SeaChem's Reef Plus and now I'm cutting xenias out weekly because they are growing too much. Also, my zoas have been spreading like crazy. Xenias and zoas supposedly do much better with sufficient iodine (which is like one of 20 or so elements/aminos in Reef Plus.) I don't know what type of salt you're mixing, but "perhaps" your weekly changes are not restoring the depleted trace elements if your brand of salt is not a high quality reef salt. If you're looking for your coralline to grow, you might want to look at your Magnesium level. Coralline absorbs a higher percentage of Mg than SPS or LPS. So it is possible that your stony coral have enough Mg to thrive but the coralline doesn't. However, it is my opinion that you shouldn't blindly add Mg without testing for it. Things like Purple Up and Purple Tech are mostly made up of Mg or you can simply buy a bottle of straight Mg.
Another tip, take a clean toothbrush and lightly brush your existing coralline. It will release spores that will land and grow in other places.
On a side note...you mentioned that you previously had a hair algae breakout. I'm not sure if you feel this was caused by the additives or not, but if so, it had to be a coincidence because HA feeds off of 2 things, nitrates and phosphates, not additives.
Best of luck and hope your dad gets better soon!
