What Kind Are Compatible?

[midnitesongbyrd]

I have 2 dalmation mollies, 1 black molly, 1 female beta, and two sun platies. I was wondering what other types of fish I could get and how many of each. I have a 20 gallon tank.

 

[Blitz]

Hi, Welcome the to the forum. I highly advise you to not get anymore fish at all. As for right now, the tank is fine. The mollies may require a tad bit of aquarium salt in their tank, read first how much to put in and if the betta can withstand the salt. In my eyes, the tank will later on be overstocked when I mollies reach full size. If you've read that mollies only get up to an innocent 3 inches, it's a LIE. They lied to you.
Mollies get about 6 inches. Some even 7. Now, think about 3 of those in a 20 gallon. No more fish, please. As for your tank will be over crowded in the future when the mollies reach adulthood. 30 gallons is better. Get more fish if you want, but I HIGHLY advise you not to.