New user here. I have a three-level home. My cable comes in to the basement, so my modem and main deco are placed there. I then placed slave Decos on the first and second floor, which indicate the basement Deco is the signal source. So far my family is happy with our WiFi speeds. 
 

Question: in the app, the slave decos' source signal strength is at the lowest bar. Should I be concerned about this? Should I move the decos around to make it stronger?