How does adding a little coldwater to a danio spawning tank help?

Question

its 5 am

i am hoping my danios will spawn when the sun comes up

someone said to add some cold water to the tank

why

Answer 1

  With many fish the beginning of the rainy season means an end to the dry season.  Food is in short supply during the dry season, abundant during the rainy season.  If they think food is scarce they will not be as willing to spawn, no food for fry, and spawning takes considerable energy from the adults.  With plenty of food this is not a problem.