Your Crystal Water Monitor comes with a trial-size tube of Insta-Test 6 Plus Test Strips which can be photo scanned for regular water reports of TA, TH, and CYA. These test strips are the recommended test strip of Crystal Water Monitor. If you run out of your Insta-Test 6 Plus test strips you can purchase more on Amazon:
Insta-Test 6 Plus Test Strips
You're also welcome to use any other test strips you may already have by comparing the colored pads to your test strip packaging and entering the numbers directly into the Crystal app.
The Crystal Water Monitor App also allows photo scanning for other brands of test strips. Here is a list of other test strips that support in-app photo scanning: