Yes, the question is I have a two part dose for calcium and alk, can I use the alk part only of the dose or do I need to purchase a separate alk booster?
As others have said just use the part you need, in your case Alk supplement
Ok, after that how do I get my ammonia and nitrite down? I'm looking to rehome two fish so hopefully lower bio load.
rehoming fish will definitely help.. Are you doing regular water changes? With your issues I would be doing at least 10% a week or even every 4-5 days, this will help raise your Alk and lower your ammonia and nitrate