Do you know what kind of frog it is for sure? Either way it will be fine with little water flow but if it's a clawed frog then I'd get rid of it as soon as you can because it will get big and eat the betta.
Clawed frogs have webbed front feet also. We have three.
Clawed frogs have webbed front feet also. We have three.
it hasn't grown any in a month only time will tell I guess.
Shrip are usually ok with Bettas so you should be ok there unless you have an agressive lil fella. Corys should be in a group of 5 plus, they are not to good in a "group" of two