pH meter together with TDS possible?

I'm using the analog pH meter, https://www.dfrobot.com/product-1025.html with an Arduino Uno, and want to measure also the TDS (via conductivity, connected to the same Arduino). Now I am wondering if the current from the TDS sensor might disturb the pH measurements if I keep both sensors in the solution at the same time. Do I have to measure one by one?

Thanks!