Molly Brown wrote:
First I would see what the ants were coming to then I would take it
away and put Grants ant traps in it’s place. The ants would eat the
poison and die off in a few days. Now they still eat the poison but I
think they developed an immunity to it because they’re not dying
anymore. Anyone else have the same problem? Maybe if I injected some
kind of poison through a long thin tube directly into their nest. Any
ideas?

Hydramethylnon has a half-life of about 10 days in soil or water.
Grants recommends replacement every 3 months indoors and every 6 weeks
outdoors.