Hi
In coco, the golden rule is to never let the substrate dry out. Here is the direct strategy:
​
​It's time for 24 days of flowering, your plant is in full "consumption".
​If the surface of your coconut is already dry after 24 hours, this means that the core of the pot is probably too dry much earlier.
​In coco, a drying substrate causes the salt level (EC/PPM) to rise drastically, which can burn the roots.
How to manage drainage?
​Yes, you should aim for drainage (runoff) with each watering.
​Why: Drainage allows salts accumulated since previous watering to be evacuated. If you don't drain during the second watering, you add salts to already concentrated salts.
​Volume: You don't need 2.5L each time. You can divide your current 2.5L in half (1.25L in the morning / 1.25L in the evening) and adjust to obtain your 10-20% drain with each pass.
​Direct advice
​Coir behaves more like hydroponics than soil.
​The more humid it is (without being drowned), the better. * At the end of flowering, some plants in 19L coco even require 3 to 4 waterings per day.
Verdict: Switch to two waterings tomorrow. One when the lamps wake up, another 6 to 8 hours later, both with drainage. I hope this will help you. Have a good evening