How Far Apart Do Betta Tanks Need To Be For Them Not To Stress About Each Other ?

How far apart do betta tanks need to be for them not to stress about each other ?

Niko and Kaido are 110cm apart and don’t see each other
IF I got a 3rd 5 gallon it would have to go between them so there would only be 37cm between Niko’s and new tank , then 37cm from new tank to Kaido’s - will this be enough ?
They are on the kitchen bench and I can’t place things there to block completely but I can put a picture frame or something there- this wouldn’t block out the whole area between tanks

 

You could also make the sides of the third tank where he/she could not see the other tanks, with paper or a background.

 

I have paper taped to mine.

 

I use a piece of paper or cardboard to block them. I like to keep them three inches apart for cleaning.

 

The 7 gallon cubes that each had a betta at one point were 3.5 inches apart.

Never had an issue with them being stressed by each other's presence.