I doubt that it’s tree roots or a break in the pipe because you are able to clear the clog.
For a slow drain, without standing water, I usually start with two pans of boiling water.
I pour the first one in and let it sit for 5-10 minutes and plunge, repeat with the second pot.
The vinegar and baking soda is the next step up followed by two more pots of boiling water.
Slow drains and maintenance are a fact of life.
Stainless steel mesh hair catchers from the Dollar Store are helpful if they work with your drain.
View attachment 474579
A zip tool, from the Dollar Store, or a hook made from an old wire coat hanger are helpful in clearing hair clogs.
Always start at the Dollar Store and work your way up!


I try to stay away from caustic chemicals because if they don’t work you end up dealing with a clog and a potentially dangerous toxic soup.
Good luck!!!