Just opened pool for spring, test result questions

[conductor500]

I have looked at a couple differant pool stores and no luck on finding the CYA reagent. I am going to order the kit off this site since I have been attending school here. The one store stopped short of telling me that the CYA was not important (maybe I was just reading too uch into it.) It would seem a "pool store" would have all supplies on hand this time of year. Anyway,since my pool has been exposed for 24 hrs. my ch. is dropping ( istill havent added anything as of yet) Ph stable at 7.2 and alk is still at 120. My next "Q" is I will leaving for 4 weeks and I am going to put the solar cover on untill I get back and wanted to know how much I should raise my Ch. before I leave?
My wife will be here to keep check on it while I am gone. Since I don't know my CYA levels will this be a problem?
Hey Dave, about that liner. If you live in Atlanta I will be there for 4 weeks come monday
Thanks for the schooling guys.
Tim
P.S. My pool is a 27' AG. Is that 16,500 gal? Need to know for use of the handy dandy bleach cal.