You could water from the top or from the bottom. From the bottom you would have to put the pots in a container and let it fill with nutritionwater and the pot would suck the water up. The downside of this is that the water doesn’t reach the top of the pot and the bottom will get to wet. A better way is to give water from the top. With this 10% of the content of your pot or container would be enough. If you see a few drops coming from the bottom it’s enough. If you work with a soil container then 10% is sufficient and to controle you could dig a little to the bottom of the container. Take a bit of soil from here and squeeze it firmly you would see a few drops running through your fingers. If you work with a soil container then 10% is sufficient and to controle you could dig a little to the bottom of the container. Take a bit of soil from here and squeeze it firmly you would see a few drops running through your fingers. Ou could also use thiks method with pots but you have to be carefull not to damage the roots. The advantage of a soil container compared to pots is also that the soil in a container is always good. In a pot you will notice that one pot is very heavy and the other is light. Because of this you really should give water individualy for the best result. So an ebb and flow system will never actually give the best results. You can water at different times. The best time is actually one hour after they wake up ( sunrise). Because then they have the whole day to process their watering. When you water depends on what your purpose is like we said before. Do you want them a bit taller and keep them wet or do you want them shorter or let it bloom earlier and keep them a bit dry. A good indication are the leaves and the soil. If your leaves start to hang it is time to water. Is your soil light of color it is a possibility that beneath the surface it is still wet. You could stick your finger in the pot and look if soil sticks to it and how it feels. You can also buy a tensiometer for in the soil if you are not that experienced. But in all cases it is better to be a little too dry than a little too wet.