You can start with one pump just for alk if you want to hold off on the expenses, as Ca swings are not detrimental by comparison.
The slimer will recover, It's a very fast growing coral and as such is one of the first effected by something like this. Make sure you bring your alk up slowly, probably a max of 1dkh per day. If you want to maintain good levels the first step is to determine how much your system is consuming per day. Once you have that number you can use a calculator like those available at www.bulkreefsupply.com to figure out how much you need to add to replenish then add that amount over the course of a day, maybe slowly over the course of 6 or 8 hours, then your daily swing should be something like 1/3 of what it used to be.
Cool I will remeasure tomorrow at about the same time to see how much I used in a day and then go from there. The calculators on bulk reef supply are really good. I had never seen them before.