Good Drainage And Aeration Begins With The Pot, Not Soil

Soil comes later. Many bonsai experts & artists 'say' good drainage & root aeration is very important, yet very strangely, some of them use pots that are poor in both areas. Though the pots shown below are tiny, the difference in drainage speed will be similar even with the bigger pots.

This classic 1 hole pot on left, gives you circling roots,  poor
drainage & hence, poor root aeration. So does a 2 hole pot. 

So, which one is your choice ? 
Multiple holes or just 1 to 2 holes ?

And filling such 1 hole pots with Akadama soil, a Japanese import, is the ultimate irony ! I prefer pots with multiple holes & hate the traditional,  poorly designed 1 to 2 hole pots.  

1 big hole vs. many small holes.

Total area of drainage holes is the same in both cases but the STUPID design on the left makes it compulsory to fix plastic mesh screens and waste time, effort & metal.

If your justification for a pot with 1 or 2 giant holes is water conservation, then please understand that you can have multiple holes of a smaller size, having the same total area as a single large hole. (Of course, the more holes on the bottom of the pot, the better !)

Tiny multiple holes totally eliminate the need for fixing mesh screens over the giant pot holes and thus, save metal & effort. Hence, wiring the mesh does not make any sense to me at all. And so many people are happily doing this for decades & probably never questioned the poorly designed pot itself ! 

  
Some have even fallen in love with this pointless ritual & twist the wires for the mesh screens, into fancy shapes, when a simple U-shaped wire is enough. They have made it into an art in itself ! 

For mini bonsai pots, even wiring the mesh screen is not needed. It is just a tiny pot, damn it ! The screen is not even having the space inside, to slip off the drainage hole. Yet I see people blindly following ancient traditions.

Those who disagree may please explain 
your logic, in the comments below. 

After being involved with bonsai for a while, I have slowly realized that the Horticultural Science part of bonsai takes more of my time than the Art part of it. Hence, in acquiring knowledge, I recommend that you too invest your time proportionately.

I watch & subscribe to many channels, including farming, gardening, plant & tree nurseries, hydroponics, aeroponics, pottery, art, manufacturers etc. Though bonsai is my only output, I have many inputs which include bonsai channels also, both professional & amateur.