Their are no dumb question hamboner just shows you care about your project.Yes i would think that the plants can absorb some nutrients without the water level dropping.Nitrogen for example is adsorbed very quickly when first placed in the reservoir and it can not even be measured with a EC/ppm meter!Excuse my dumb ignorance here but can the plants absorb the nutrients out of the water without the water level dropping?
like i said sorry if it's a dumb question im new to DWC ,my first grow after a few years of soil.
cheers for any advice.