sick fast and vast plant

[Waira]

that A8 unit is the ticket, but in a pinch, a pH meter and the run-off test/calculation is the only other option,... typically, this method is full of measurement error, but if you follow this guide closely, you can get a decent reading-- https://www.autoflower.org/threads/...-testing-and-ph-estimation.41733/#post-928975