Can mollies live with assassin snails?

Verdict
Yes

Yes. Mollies and assassin snails get along in the same tank. Both are fine at 75–80°F. Plan on at least 20 gal.

MollyMolly72–82°F · pH 7.5–8.5 Assassin snailAssassin snail75–80°F · pH 7–8

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 75–80°Molly 72–82°Assassin snail 75–80°
The green band is the temperature range both can live in.
456789Both: 7.5–8Molly 7.5–8.5Assassin snail 7–8
The green band is the pH both tolerate.

Size to scale

Molly · 4 inAssassin snail · 1 in0"1"2"3"4"5"6"
Adult length in an aquarium. A fish can swallow anything that fits in its mouth, roughly a third to half its own length for predators.

Care at a glance

MollyAssassin snail
Temperature72–82 °F75–80 °F
pH7.5–8.57–8
Adult size4.0 in1.0 in
Minimum tank20 gal5 gal
TemperamentPeacefulPeaceful
Swims atTopBottom
GroupGroups of 3+Alone or in pairs
DietOmnivoreCarnivore

Better tank mates for mollies

All molly tank mates

Better tank mates for assassin snails

All assassin snail tank mates

Questions

Can mollies live with assassin snails?

Yes. Mollies and assassin snails get along in the same tank. Both are fine at 75–80°F. Plan on at least 20 gal.

What temperature suits both mollies and assassin snails?

75–80 °F. Mollies need 72–82 °F, assassin snails need 75–80 °F.

What size tank do mollies and assassin snails need together?

At least 20 gal, set by the molly. Add space for each extra fish.