Tired of guessing whether your water’s nutrient levels are adequate? Hydro Rx takes the guess-work out of water management. Hydrofarm Test Lab has developed a kit that lets you manage your plant nutrients with lab-tested precision. Hydro Rx is simple: just take a water or soil sample and send it back to Hydrofarm Test Lab in the enclosed mailing envelope, and within 2-4 days, you’ll receive a detailed analysis of your plant’s water. Test results are available online or by email.