Questions From A Newbie About Mollys

Woah! One molly in that tank is enough! As for it being sick you should probably add a fourth of a teaspoon of aquarium salt in there. Please continue doing research on this site you got a lot to learn! As for the flakes just feed a few twice a day. By the way(2 things) #1 your pet store is on crack!~don't listen to them! And do you have a heater in your tank? The temp should be about 78degrees. I really think you should get at least a 5 gallon because really the only fish that can live in that tank is a betta(only 1!) Maybe return the molly and get one, they have lots of personality belive it or not! But the best thing to do is go for a 5+ gallon. Good luck and remeber to research!

A 1g tank is too small for 1 mollie, some mollies can grow over 4" and they are quite active. A dalmation mollie usually don't grow to over 3" but that's still too small a tank. If you want multiple mollies, I suggest a 20g tank.

A fish swimming and shaking in one spot can be what is called shimmying, an indication of stress. Check your water parameters (ammonia/nitrite/nitrate).

Feed the fish once a day, just a pinch. If there is food left after a minute you are overfeeding.

I would see if you can return the molly and second the suggestion for a betta. They are really pretty fish and have quite a bit of personality.