Something is eating my orchid roots!

[adalberto09]

Hi everyone. Something has been eating my new orchid roots for quite some time (Vandas, Phals, Catts). I've always thought that the lizards are what's doing it. I asked for advice from someone that knows WAY more than me and he says that insects are what does this. He told me to use Malathion. My question is, what's the best time to use it and should I fertilize the same day, next day or a couple of days later?