I've got springtails too. I did a lot of reading about them and have done the following, whether they are harmless or not.
Firstly, I notice that mine look like a cluster of mini grains of white rice. I didn't see that aspect mentioned anywhere.
I also read that mosquito dunks are supposed to work. I've had one in the res. for over 48 hours and I don't see a difference.
In my second smaller garden, which I didn't think was infected, but it is, I am able to try other solutions, because I just harvested and that means cleaning and disinfecting time anyway.
I flushed all the water from the drain pipes into the res after emptying the majority of water from the res. The remaining water that drained from the pipes into the res was crammed full of springtails. I poured vinegar on them and they were dead within 15 minutes. Once I have cleaned all the bins and set up the system again, I will flush the whole system with a strong vinegar solution and then rinse a couple of times to neutralize the pH again. That should kill anything in the pipes.
The big question is how to kill the springtails in the big garden which is 1 month into veg. I don't want to harm the plants with a vinegar solution now. If I wait and vinegar (douche) my bins after flowering, I risk allowing the infestation to return to the small garden. I don't think $20.00 of mosquito dunks is working.