Can mystery snails live with harlequin rasboras?

Verdict
Yes

Yes, mystery snails and harlequin rasboras can live together. Both are fine at 72–80°F. Plan on at least 10 gal.

Mystery snailMystery snail68–82°F · pH 7–8 Harlequin rasboraHarlequin rasbora72–80°F · pH 6–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–80°Mystery snail 68–82°Harlequin rasbora 72–80°
The green band is the temperature range both can live in.
456789Both: 7–7.5Mystery snail 7–8Harlequin rasbora 6–7.5
The green band is the pH both tolerate.

Size to scale

Mystery snail · 2 inHarlequin rasbora · 2 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

Mystery snailHarlequin rasbora
Temperature68–82 °F72–80 °F
pH7–86–7.5
Adult size2.0 in2.0 in
Minimum tank5 gal10 gal
TemperamentPeacefulPeaceful
Swims atBottomMiddle
GroupAlone or in pairsGroups of 6+
DietOmnivoreOmnivore

Better tank mates for mystery snails

All mystery snail tank mates

Better tank mates for harlequin rasboras

All harlequin rasbora tank mates

Questions

Can mystery snails live with harlequin rasboras?

Yes, mystery snails and harlequin rasboras can live together. Both are fine at 72–80°F. Plan on at least 10 gal.

What temperature suits both mystery snails and harlequin rasboras?

72–80 °F. Mystery snails need 68–82 °F, harlequin rasboras need 72–80 °F.

What size tank do mystery snails and harlequin rasboras need together?

At least 10 gal, set by the harlequin rasbora. Add space for each extra fish.