Temperature Required For Shrimps

I have kept Cherry shrimp in a nano tank similar in size to yours. They were kept at room temperature. I think 18 C is the minimum for them. The tank is now defunct and the shrimp are in my main tropical tank in which the temperature is maintained at 25 C.
The nano tank was planted with Java Moss which they love rooting about in.

Red cherry shrimps need a temperature between 22 and 29 ^oC (72 to 84 ^oF)

Heaters with a temperature adjuster are much safe than those fixed temp ones. For 5 galls you will need to choose carefully as some brands will be too long.

I can't remember where I found this now... it was a couple of years back but I've had it saved since... it's in Fahrenheit though:

Above 89, expect dying shrimp within hours.
Between 83F-88F is too warm for their likings, but will survive.
Between 68F-82F the shrimps do best, breed well.
Between 59F-68F shrimps do fine but breeding stops as temp. drops. Is fine for nightly temperatures.
Between 50F-59F shrimps survive but don't breed
Between 40F-50F shrimps survive but life gets tricky
Below 40F for a short period this is survivable, expect losses up to 90% if temp is below 40F for weeks.

Thanks Matt, that is worth saving, think I shall save it too, for future reference.