Boy, it sure would make it easier for you if you didn't have to rely on the pool store for testing! We like the Taylor K-2006 that you can find a lot of places. This link shows a place that has a good price for it.

http://www.amatoind.com/taylor-k2006-test-p-555.html

If you are able, it would probably be a good idea to invest in a good kit. It will pay for itself in no time!

Add more bleach tonight.