Hi Nature Fish! Welcome! I began a journey exactly like yours then learned everything I was doing wrong and now I'm struggling to correct it and save my mollies.
Things I learned the hard way:
1. Mollies really need more space than 10 gallons. 30 gal
is recommended. I'm struggling with mine in a 20 gal
after starting them in a 5 gal
2. They are the MOST sensitive of the live bearers and need very well kept stable clean water. Slow acclimation is important and regular water changes a must!
3. If you buy females, they will most likely be pregnant and will have babies in your tiny tank.
4. Live plants will help keep your water parameters stable, but you can not use aquarium salt.
5. An API master test kit will be necessary in order for you to keep your water pristine. The strips really are not clear enough nor are they very reliable.
6. The Dalmatian mollies seem to be even more finicky than the rest. Perhaps wait to add the Dalmatian until the others have survived a few weeks.
7. Read, research and read more. The information on this site is amazing and everyone is very helpful.
Those are the big ones I've learned the hard way. I am absolutely loving this hobby, but I fell into it completely unsuspecting.
Best of luck with your tank. I love my mollies, but if I knew everything that I know now when I started, I would've had a much easier time and probably wouldn't have lost as many fish.
I hope this information is helpful and saves you much grief.
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