What technical skills and training do I need before starting hydroponics?

Hydroponics is skill heavy and the technical side is where most beginners come unstuck. At minimum you need to understand nutrient solution management, meaning EC (nutrient strength) and pH control and how to correct them daily, crop-specific nutrient recipes, water quality and the need to treat hard or saline water, disease and root health in a recirculating system where one infection can spread fast, and the climate control of the structure the system sits in. You also need basic comfort with pumps, timers, and dosing equipment, and a plan for power failure. None of this is impossible to learn but it is unforgiving, a wrong EC or pH or a pump failure can damage a crop within hours, unlike soil which buffers mistakes. Do a proper hands-on training, ideally a few weeks at a working farm or a recognised course, before investing. Many failures trace back to people who built first and learnt later. Check with your KVK or state agriculture university for protected cultivation and hydroponics training options.