Hi I have a hibiscus that I repotted an brought inside for the second winter. it got too big for it's pot and stopped flowering. I'm trying to get it to flower with fish fertilizer that I just added today. Well, several hours after I did that there were dozens of little millipedes or a similar bug on the top of the soil. I never noticed this before today , so I dug them out as best I could. I do see a few more. Does anyone have a suggestion for an insectiside to add to the soil, or some other suggestion?

i read somewhere to submerge the pot in water so them swim to the top to look for air and then they'll just go down the drain.

Any suggestions are helpful.