I have a fluval flex 9 gallon that’s been set up for 9 months. What would be a better nano fish for this tank? It has decent flow but I slow it down by turning the outlets towards the glass and back of the tank. I was torn between choosing celestial pearl danios or chili rasboras. Which one is less timid and more likely to show off its colors without hiding as much. Also how many could I get of each? Thank you for any help!