Rams, Amano shrimp, and tetras?

The rams need less space than boesmani, which need at least a 4 foot tank. Boesmani also have very small throats.

So rams it is. How many for my tank and what male to female ratio?

How many cherry shrimp do you have? How planted is your tank? I have a 20L that's heavily planted, I also have a healthy cherry shrimp population (50+). That being said I have 2 pairs of GBR and a female Betta, some neon tetras and guppies, every once in a while I'll see a half eaten shrimp. But for the most part everyone gets along fine and the shrimp population doesn't seem to be dwindling. If u have hiding spots you should be ok. Btw I also have 3 Alamos, but I never see them out side, I only know I still have them when I see their molted shell

Sent from my HTC One using Tapatalk

Yeah I have 100+ cherry with rasboras and reall big momma guppy, she doesn't bother the mid size shrimp. I also have bunch of baby shrimp that roams freely.

I also have had success with keeping two pairs of GBR's in a heavily planted 20L with success. I didn't have a betta in there but they seemed to carve out there own spots on each side of the tank. And I have shrimp in every tank I have except for larger fish like geo's and like OAli said from time to time they will pick off a shrimp or two but not enough to affect the population. If you have all males it you shouldn't have any problems as there are no females to fight over but they'll figure out their pecking order. If you get females as well, I wouldn't get more males than females as someone will always be getting picked on or left out. I'd say a pair or two.