Have you added CYA to the pool? Your SWCG manual should have a suggested level for CYA. If there is no CYA in the pool, you won't be able to keep a chlorine reading. CYA is kind of like sunscreen for your chlorine. Without it, your chlorine is quickly lost to the sun. So, if you don't have any CYA, even if your SWCG is producing chlorine, it isn't gonna stick around for long.

You actually are supposed to get your water balanced before you turn on the unit.

You need a drops-based test kit, no test strips. (We don't call them 'guess-strips for nothing!)

The kit we recommend is the Taylor K2006 or 2006C (better buy). The kit is not available locally but you can get it through this link that takes you to Amazon: http://pool9.net/tk/

Tell us what all you have added to the pool, meaning ingredients and not just product names.

Then, someone here can better advise you.