Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
I would not think so.
Put a little bit of each thing from the tank into a separate jar of water. One jar would have a handful of the substrate, another would have some driftwood, or rocks (whatever is in the tank), and another would have nothing, just the water.
Test each for GH, KH, pH and TDS every few days.
Plants use many minerals that are in the water, but that is a big drop in TDS. How fast does this happen?
If you did a water change today, and tested the TDS daily, would it show up right away?