Am using a 330ml pot with coco coir when do I feed...

depends

In coco, I usually start feeding the seedlings with a very light nutrient solution as soon as they have their first true leaves, usually around day 7–10 after germination. Coco can be tricky for beginners since it has no nutrients at all and needs proper pH control. I recommend starting with 1/4 of the recommended nutrient dose and keeping the pH around 5.8–6.0. For the first few days, I just mist the top layer lightly with a spray bottle, no heavy watering yet because the roots are still tiny. It’s always safer to underwater than to overwater in the early stages. As the plant grows and develops a stronger root system, slowly increase both the amount and frequency of watering. 🎅🎅🎅