Pea puffer group size

[Liddojunior]

So I bought a group of 5 pea puffers to raise until I could determine which are make and female. Plan was for a trio in a 10 gallon. 
 

Currently I found they are hard to catch. They are fast and hide well. If there are no signs of fighting, no torn fins or injured puffers. They tend to patrol together and then separate to their own little spots. Is it okay to keep 5 of them in the tank? 2 males and 3 females. 
 

There isn’t a clear line of sight anywhere in the tank because of how dense the plants are. I kinda want to give up scaring them by trying to catch them and leave them be. I’m always throwing in live worms, bb, and snails. They don’t see me as a food source so they get scared if I try to feed with tweezers. But they seem to be happy and have gotten bigger than I thought they would be! 

[Rxhart]

General rule I have read is 1st puffer needs 5 gallons, and 3 gallons per puffer after that.  So a 10 gallon could hold 2-3 by that rule.  Best 1 male and 2 females.  Good luck catching them!

(I have a group of 8 babies in my 20 long trying to sex as they grow, too. I am going to separate them once they are sexed into 2 aquariums.)

[Odd Duck]

My 9 (2 males and 7 females) that I put into my 29 gallon have slowly diminished down to 3 at last count but I have a bacterial bloom going and haven’t seen a puffer in a couple days.  They may be gone.  Nobody gets along and they were raised together from very young juvies.  They actually bred in quarantine because I found fry in the QT after I moved the sexed subadults into the 20 long. I was hoping I would see breeding in that tank since it was heavily planted, but never saw a single fry.  I moved the group to the 29 G that was even more heavily planted with mosses and never even saw anything that looked like a pair develop.  Perhaps I inadvertently split up the pair when I picked my shoal?  I’ve been very disappointed in shoal development and have backed away from recommending larger shoals. I was more successful keeping a single asocial male in a 6 G cube than anything else with pea puffers.  I haven’t found the perfect setting for peas.