Can rams live with killifish?

Verdict
No

No. Rams and killifish should not share a tank. No shared temperature. Rams need 80–86°F, killifish need 70–77°F.

German blue ramGerman blue ram80–86°F · pH 5–7 KillifishKillifish70–77°F · pH 5.5–7

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°German blue ram 80–86°Killifish 70–77°
The ranges do not meet, so one of them would always be too warm or too cold.
456789Both: 5.5–7German blue ram 5–7Killifish 5.5–7
The green band is the pH both tolerate.

Size to scale

German blue ram · 2.5 inKillifish · 2.5 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

German blue ramKillifish
Temperature80–86 °F70–77 °F
pH5–75.5–7
Adult size2.5 in2.5 in
Minimum tank20 gal10 gal
TemperamentPeacefulPeaceful
Swims atBottomTop
GroupAlone or in pairsAlone or in pairs
DietOmnivoreCarnivore

Better tank mates for rams

All german blue ram tank mates

Better tank mates for killifish

All killifish tank mates

Questions

Can rams live with killifish?

No. Rams and killifish should not share a tank. No shared temperature. Rams need 80–86°F, killifish need 70–77°F.

What temperature suits both rams and killifish?

None. Rams need 80–86 °F and killifish need 70–77 °F, so the ranges do not meet.

What size tank do rams and killifish need together?

At least 20 gal, set by the german blue ram. Add space for each extra fish.