Leaves

its a lack of calicum and magnesium biobizz always needs some calmag biobizz sell a calmag supplement thats your best bet its quite cheep use no more than 1ml per 1l every feed and that should do it. if you happen to be short on funds their are other things you can use for organic calcium dry some eggshells in the oven on its lowest setting overnight, crush them into a powder sprinkle the powder on the soil as a top dress for the magnesium you can use Epsom salts witch are basically magnesium sulphate 1 tsp per 1l max its important the plant gets both calcium and magnesium because an imbalance between calcium and can cause problems with how the plant takes in nitrogen the nitrogen is used to produce the chlorophyll that the plant uses to convert light into energy chlorophyll is what makes leaves green without the right nutrition the plant doesn't produce new chlorophyll fast enough https://www.growweedeasy.com/common-nutrient-problems

Nutrient issues of some kind. Its possible your soil and/or water PH is off and needs to be fixed, or it is possible you are feeding and/or watering too much. Its hard to underwater, and in soil (assuming its organic and not straight coir and perlite) it is rare that you need to actively add nutrients to the plant. While its hard to correct while growing, if you start with good organic soil and feed it lightly once every one to two weeks with compost tea and only water 2-3 times a week max (or set up a wick system) you shouldn't need to worry about anything all that much.