Each plant is an individual living thing. Each one will have its own water needs. And the water needs will change as each plant grows so it is possible that the 330 ml might not be enough for some and too much for some of the others.
Read all the way though the link on the messages in the "Proper Way to Water A Potted Plant" thread. Over the years some of the points mentioned have been modified or changed. New ones introduced and some dropped.
Then, there are changes in the amounts that are needed based on the stage that the plant is in. Some growers have had to change the amounts they use and the frequency based on the stage of growing that the plant is in, especially once it enters into its flowering stage.
