Springtails Won't Go Away

[Dmwesq]

For the last couple of weeks we have been seeing a large amount of tiny springtails in both the shower and sink in one bathroom in our home. They don't seem to be an issue in our other bathrooms. I have tried several times to pour a mixture of baking soda and vinegar down the drains, and the last attempt last night included some salt and I used apple cider vinegar, but the problem persists.

It is hard to figure this out. The sink drain is all new parts, at least up to the wall, so there isn't a build up of gook there. I have cleaned the pipe beyond the wall as best as I can, but am certainly open to suggestions as to how to clean the hidden pipes better. I know a snake would clear out a clog if one existed, but not sure it would clean the sides of the pipe like a good brush would. Do they even make a brush that you could insert along the pipe to scrape it clean?

Back to the shower, the drain has a crossbar that the drain cap screws into, and I can't even get a brush past it to begin to clean that drain. Just looking for some thoughts here.

 

[Reach4]

Did not know that word. https://en.wikipedia.org/wiki/Springtail

I would consider some liquid chlorine bleach. Then cover the drain hole.
If that does not do it, I would try insecticide. I like a little aerosol can of Raid. I think aerosol cans are good... product seems to stay good for decades vs less-sealed containers.