Ph in soil when feeding sythentic nuteients

You should always ph your feed and water. Most cases the soil is slightly acidic, most plants prefer it.

a good "synthetic" should be ph-buffered. consider a different brand if it is not.. saves a lot of needless headaches.

yes u need to buy 3 in 1 Measure Soil pH Level, Moisture Content, Light Amount Soil they cost around 15-20 eu but if u mixing nutriments is better to mix them in water and after water the plant with that water or they are some nutriments who u just need to place on the top of soil and with every watering they go down