poolmath calculator

Hi everyone! New here, first post, please be kind haha. After 1.5 arduous weeks of trying to get my pool filter up and running without flooding the entire block, I have finally attempted the impossible and this Frankenstein is alive! (I got 75% of a Bestway power steel 24x12 with sand filter...

Is it true that the free version of PoolMath app only allows you to record a single set of tests? Because when I clicked the "+" sign on to add another round of tests the next day, PoolMath wanted to sell me a premium subscription. I don't mind spending $7.95/year on a good app, I need more than...