In article ,
Danny D'Amico wrote:

What works best for mouse/rat/gopher poison & in what concentration?

No one has mentioned that dead rodents have a foul smell that lasts a
long time!

After using the blue crystals and having the long lasting smell, I found
a rat poison that looked like a fat granola bar. According to the
dealer where I bought it, the rats eat it but do not die right away.
They become thirsty and have to go outside to find water. The poison
kills them when they drink, so they die outside.

I don't know if this is description is correct or not, but it got rid of
the rats with no odor. This was from five or ten years ago, and I do
not know the name of the poison.

Fred