Provided you stick to the rules they are compatible. The basic rules. :- 1 inch of fish needs a minimum of 1 gallon of water. :- Every tank needs a permanently running cycled filter. :- Every tank needs at least 50% of its water changed every week. Keep the above rules and your fish stand a chance. Fail in any of them and I can guarantee that you will have constant health problems with your fish.
They can not go with there own kind but do well with guppies and larger fish...
no
What are guppies
yes.
Yes - there is virtually no limit to how many female guppies can live together.
The male chases the female around and tries to go under her while the female runs away.
sounds like you have a male guppy harrassing a female. Simply go and buy a few more female guppies and that way the male will have more than one female to harass.
Female guppies stay very plain to help with camouflage. Male guppies get color to attract females.
You do not say if the guppies are common guppies or fancy, also how many male and female guppies you have, yes as far as the snails and guppies go, one point to remember is the tank water should be above 72 degrees and some live floating plants for the guppies too hide in.
Male guppies are considerably smaller than females of the same species.
Don't own female guppies if you don't want youngsters.
Yes, because guppies will eat their newborn fry.