Lowes is not going to have what you need but you don't have to spend a lot of money. You can get by with a $5-$10 "color chart" pH tester from the pet store until you can get one from ebay or somewhere like that. A decent pH pen (for testing water) is only about $20-$25 from any number of places on the net. Let me know if you need a link. You'll find the color chart kits in the aquarium section of any pet store. The problem with the color chart is that you can really only tell what "range" your pH number is in... not the actual number. Also, it is only accurate when testing clear water. So, you can't buffer your fert solution with it.