Yes, That is definitely enough space
The African dwarf frog can indeed live with fish in a five gallon aquarium. BUT BEWARE!!! dwarf frogs may eat your fish small enough to fit in it's mouth. so i recommend Platy and live-bearers as companions.
Any.
betta fish like at least a 1 gallon tank (nothing smaller) > They can live in a community tank but with no other bettas.
tell more about why its not breeding what is its behavior Mabe the platy tank is not suitable for the platy pair try adding more plants and hiding spaces for the fish and feed them more of a variety of foods flake + blood worms+live or frozen foods if possible
length and width for a 55 gallon fish tank
They do mate! As long as you have 3 females with 1 male and you keep the tank well planted and at the right temp!
probably a 50 gallon tank would be best.
Neons
The only fish you can keep in a 5 gallon tank is one betta (Siamese fighting fish) on it's own as that is a very small tank.
It deppen on your tank size: 2.5g tank: 1 betta or 2 platy or 2 mollies
A 20-gallon tank can comfortably house around 4 to 6 molly fish. It is important to consider the size and behavior of the fish to ensure they have enough space to thrive.
YES