This is my 2nd DWC run. First was Power Kush in 15liter tubs. This is Critical Kush in 30liter tubs. I'm about 45days into flower. I start with Prop-O-Gator, Move to weak Canna with slight Silicon+ supplement, Add 1/2 strength PK13 later in flower, Trying out a weak dose of Sugar Royal this run. Both times nutrient demand steadily increases as the plants grow, like you'd expect. I need to mix up extra nute solution for keeping the reservoir topped up. Then things shift. Demand for water continues to increase, but the nutes really slow down. I have to switch to topping up with plain water to keep the concentration manageable.. Plants show no signs of distress, there's been no major environmental change (temps have gotten more comfortable recently). So is this just a normal thing? It makes the idea of flushing seem a little redundant if the plants themselves stop sucking nutes anyway.
Yep normal aslong as you have accurate monitoring of your ppms, you should be striving for a balance/incremental decline of ppms. Ppms= dissolved solids in your mix What you want is the plant to take those disolved solids from the water. If your plant is leaving those solids(salts) in the mix and taking water more than you know that the mix is too strong for the plant.
Yeah it's completely normal and yeah it does make flushing a little redundant in DWC. Flushing is for soil growers, flushing the soil prevents the plants getting overdosed. You can't really flush a DWC anyway, there's nothing to flush. I prefer the term refresh, and you set the ppm to whatever the plant is taking up anyway