Can red tail sharks live with boesemani rainbowfish?

Verdict
Yes

Yes. Red tail sharks and boesemani rainbowfish get along in the same tank. Both are fine at 75–79°F. Plan on at least 55 gal.

Red tail sharkRed tail shark72–79°F · pH 6.5–7.5 Boesemani rainbowfishBoesemani rainbowfish75–82°F · pH 7–8

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 75–79°Red tail shark 72–79°Boesemani rainbowfish 75–82°
The green band is the temperature range both can live in.
456789Both: 7–7.5Red tail shark 6.5–7.5Boesemani rainbowfish 7–8
The green band is the pH both tolerate.

Size to scale

Red tail shark · 5 inBoesemani rainbowfish · 4 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

Red tail sharkBoesemani rainbowfish
Temperature72–79 °F75–82 °F
pH6.5–7.57–8
Adult size5.0 in4.0 in
Minimum tank55 gal30 gal
TemperamentSemi-aggressivePeaceful
Swims atBottomMiddle
GroupOne per tankGroups of 6+
DietOmnivoreOmnivore

Better tank mates for red tail sharks

All red tail shark tank mates

Better tank mates for boesemani rainbowfish

All boesemani rainbowfish tank mates

Questions

Can red tail sharks live with boesemani rainbowfish?

Yes. Red tail sharks and boesemani rainbowfish get along in the same tank. Both are fine at 75–79°F. Plan on at least 55 gal.

What temperature suits both red tail sharks and boesemani rainbowfish?

75–79 °F. Red tail sharks need 72–79 °F, boesemani rainbowfish need 75–82 °F.

What size tank do red tail sharks and boesemani rainbowfish need together?

At least 55 gal, set by the red tail shark. Add space for each extra fish.