If ya have a shitty soil mix it will save all the water.You need a good mix and make sure the planter has holes in the bottom.That may sound stupid but some people would rather not put holes in the planters.Next question,oxygen i always pump air through my nutes and water its refreshing for the plant
You usually need a sphagnum mix.But as long as the roots can aerate youll be ok.1st signs of drowning are drooping leaves and twisting leaves like the plant has died.if you wait til the plants are dry and just start drooping then water youll have a better root system.The bigger the roots the bigger the fruits!!!!!!!bdw