Possible molly fish pregnant?

have a dalmatian molly who i believe is pregnant..she looks different than my other dalmatian molly.she is bigger and fuller looking..chases my male fish and nips at him..very well she has a black dot on her belly close to her anus hole..and her anus gap is opened up..you can really see it, it is very obvious that it is open up..is this normal?? do pregnant fish have their anal vent get bigger and open up more? my other molly is slender and his anal vent is normal looking..kind of small..but my female..wow..hers is really start on..she is a dalmatian so i cant see a gravid spot..just a black dot on her belly close to her vent..please help me next to this! i have never had fish before..also her anal fin is not a seashell looking fin..its alot shorter than my other molly but does not adherent out..its looks like a male and female fin..i cant explain it..is it common for a female to not fan out her anal fin? any info would be great! and 10 points best answer!
Does anyone know how tons pet grooming...
Answers:    This should be in the Fish screened-off area, you will more answers there.

Good luck.

Lily
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