What size tank ?
Fish stores will sell you anything and say anything to make a sale often times. Mollies, especially the females, get quite large. I usually don't advise them for anything under 30 gallons.
One of the most important pieces of equipment you should have is an API master test kit. You need to make sure that ammonia especially, is kept within reasonable limits, or your fish will die.
Articles you should read ASAP
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Please don't add more fish till you learn more about cycling a tank.
Your fish are very nice looking BTW.
We'll try to help keep them alive.
If you have any interest in Live Plants, we have a section on that. Plants can help your cycle go smoother for the fish.
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