My tank is beginning to have what could turn into a major algae problem, and at 3.5 gallons, is far too small to have cory cats, otos, or any other fish, for that matter. So, I'm thinking of getting a pair of Amano shrimp to clear up the problem, but will a grown male betta and the two shrimp be overstocking for a 3.5 gallon filtred + planted tank with two 50% water changes per week? I understand that the Amanos tend to get a lot larger than RCS (red cherry shrimp), and most other shrimp species, for that matter - however, they're supposed to consume every type of algae imaginable.
Also, are there any diseases I should be worrying about that are transmissible from shrimp to fish? And I thought it would be worth mentioning that my betta is of the very laid-back sort. He probably wouldn't fight back much if the shrimp decided to gang up on him, and being a relatively small adult male, I have real concerns about him winning a fight against two large shrimp. I'd prefer just getting one shrimp, but everything I've read suggests that it's a bad idea to do that.