Yellow tips upper/newer growth

It's a minor nute burn. See how dark green are the leaves? That means that you have too much grow nutes (or that the soil is too hot) stop all feeding and only resume when you notice some nutrient deficiency, let the soil feed the plant

Thanks guys for your answers. Today I watered with just plain PHed water at 6.5, I had a little runoff and I took the occasion to check it's ph as well, which was 6.0. In the meantime I ordered a soil ph tester. I'm going to try the suggested water-water-feed schedule, reducing the amount of nutrient for the next feed back to 0.4. I will let you know if the situation will improve, thanks again :)

Hi @RKERKE it seems to me to be variations in PH and may be the beginning of a slight lack of magnesium if the leaf tips in the future burn and curl upwards. But it seems to the lighter new growth is chlorosis .The chlorosis symptoms show up on new growth because the older growth has already established its chlorophyll content. When the plant attempts to produce new leaves, there is not enough iron available for the plant to create a healthy green leaf. Nothing to worrie about . They look great. Good luck mate 🙏👍

Looks like nute burn, mix up Ur batch with the same amounts then add an extra ltr or if you can't fit it tip out 1.5 ltrs and add 1.5 ltrs of water the mix And adjust the ph