i'll try to help you..my tank stays a constant 430.. i do a 5 gal water change every week and dose calcium ( cant remember which one as i dumped it into a pump bottle that give me 5 ml's a pump) i use 3 pumps every other day unless i reach a maxium of 60ml a week. Coral line is good for your tank.. If your coral line is growing then its out competeing your other bad algae..380 is getting down there..it needs to be brought up to at least 400.what coral do you have in there again..anything with a skeleton will use calcium.. hammers, acans, favia, just a few of what will use calcium. i Hope that helped

Rick