You might want to check with WalMart--they used to have a 6-way test for around $15 that tests for Cl, pH, Alk, CH, TA, and CYA. The ones around here don't carry it anymore but I've seen posts on the forum from other parts of the country where they do still carry it. While you're at the pool store, look for a good drop-based kit that tests for those things. The Taylor K-2006 is the kit we recommend, and they can be found online or at some pool stores. They can be kinda pricey (up to $100), but believe me, they will save you that much money hundreds of times over when it comes to maintaining a clean, clear pool. When you have your water tested, make sure you get a reading for CYA and Calcium hardness--they're going to be important in your pool and I didn't notice readings for either of them in your above post.

About the aeration in your pool, you don't necessarily have to run the pump longer than normal to raise the pH again, but it won't hurt. It's a gradual process. You can point your return eyeballs to the water surface in order to create rippling in the water, and that will help. A large group of kids splashing around in it will help even better! Just make sure that when you add the acid, you're adding it in front of a running return, and don't add enough to drop the pH lower than 7.0. Be patient and act slowly, with this and all chemicals, because it's much better to "sneak up" on a target than to overshoot it and have to correct problems later. If you overshoot and drop the pH too low, you can always raise it fairly quickly with Borax, but don't want to risk doing any further damage to your pool than the previous owners already did.

Janet