Usually plants beeing droopy is need of water, but after they had 600W for 18h or after being outside at a very sunny and hot day, sometimes they can look a little bit droopy even if the soil is still not very dry.
If you water them every second day 'till at least 10% of what you fill in runs out at the bottom it's usually fine...
The need of water with/nuts increases as plants are growing, if every second day watering slowly untill at least 10% is running out at the bottom is not enough, you should consider to transplant into bigger pots...
Lot of peps will tell you not to overwater or not water too often...
But when Plants allready have lots of roots and if you have good soil wich lets drain out what's to much, it's usually difficult to over water them...
Just when plants are very small and still have few roots, or if the soil is not good, it's easy to overwater...
Watering 'till some water or nutrient solution drains out has other benefits too.
It helps to maintain more stable the PH of your soil, and it helps a little bit like flushing to wash out a little bit the salts and minerals, and whatever else that's in the soil your plants don't need anymore. Usually this makes flushing almost unnecessary.
