What deficiency is this?

Yo regularía el PH a 6.2 con una ec no superior a 0.9 y aleja la luz del foco, evita quemaduras. Riega con un 10% del tamaño de la maceta. Por ejemplo, maceta de 5 litros regar con 500 o 600 cl y deja drenar el agua sobrante. Tira ese agua que sobre, no dejes que la planta se lo tome. Espero que te sirva de ayuda. Suerte

Not a big fan of Plagron, its confusing at best. Seen a few questions regarding their products. This looks like magnesium to me. can use epsom salts to fix it real quick. 1tsp in 1gal. Good Luck!

Ah plagron told you like that ;) Well i also used royal and batmix a few years back and i have had the exact same problem. I never knew when to start with the feeding to have a smooth transition from the soilnutes to bottled nutes. It might be interesting to look into Premix (biobizz) or Supermix (plagron). these are dry nute mixes which u can mix yourself. If you start of with nuteless soil or a lightmix u can mix like 3 to 5% of these dry nutes into your soil and u dont have to worry about feeding anymore for the whole run. Ofcourse this also need some fine tuning like everything else but it takes away alot of hassle. Also this is organic like it should be instead of bottled up stuff. You dont have to adjust your pH nomore because of the ph balanced nute mix. I think there is even some mycco in there but im not sure. Now, u said your pot is 11L and with a plant this big/small i dont think it can be a nute problem like u said. It looks like cal/mag to me too. I might think its due to light stress, can this be? Idk if you have some knowledge about PPFD but a plant like this probably only need max 400 ppfd. Led lights can be extremely strong. In jour journal i see you use a 250W led light at 50cm distance. If you dont have your light dimmed this is probably the problem but im not completely sure. Is this the only plant underneath this light or are there more? Good luck

@HolyHerbs Plagron has a calculator where they also ask for pot size which is indeed 11l as you guessed. The reason I’m suspecting Mg instead of a general deficiency is that the substrate is heavily pre-fertilized and should last to week 6 in theory. But your answer motivated me to do some more EC tests of the substrate. Would you go with the Plagron Alga Grow for now or would you start using the Alga Bloom right away? I just thought that with a substrate like royalmix the experience would be more hands off, just add water since everything should be in there in the correct quantities. Guess that’s not the case.

Plagron can only tell you when to feed if they know what kind of potsize you are using. I have no idea what size im looking at but it seems like about 11L, am i correct? If i were you i would just try some usual grow nutes first before trying to solve a solo difficiency problem. I can only say what i should do and this might seem a bit controversial but i would try about 2 or 3ml a l for 1 watering. This might be too much if u are going to do this watering but the idea is to focus on how the plant will develop after this injection of nutes. It should be getting green again from the inside leafs. If your leafs get a burned edge the amound of nutes was just too much and if they stay light green/yellowish it wasnt the problem. If they also burned but the plant is getting green again u can confirm ur problem and just do a little step back in nutes to balance it out. This might seem simple and it quite is but if you dont do this first then u might end up now knowing what u have tried and so on. Like u stated ur pH is fine, thats the starting point. then i would go for usual nutes, then dive into the defficiency maze :) Hope this helps a bit, good luck