Great idea! Thank you for sharing!

thanks will give it try when I bring in the trees

Silica, how much do you actually have to use, and do you think its also safe on container chilies? I've had a serious gnat problem this year and the constant rain certainly doesn't help.

Whoa, need to check if I can find some similar stuff from here.

Happy though I got soil-mites, I just have no clue from where, but they helped me out of a serious gnat invasion. Now all my plants have them after I moved soil from container to another. One or two knocks on a pot and they raise to the surface, hundreds of them per plant. You with many plants should check out if you can buy some soil-mites somewhere.

I used to have springtails too on the saucers, but they have vanished too.

Gnatrol (https://www.valent.com/Data/Labels/2012-GNT-0001%20Gnatrol%20WDG%20-%20form%2004-6746%20R3%20&%2004-6747%20R3.pdf) has the same active ingredient (Bacillus thuringiensis bacterial spores) but is formulated specifically as a soil drench for potted plants. I do not know if it is more expensive to use than the Mosquito Dunks.

By the way, fungus gnats are indicative of a medium whose surface has not been allowed to dry. I rarely get them and only on the 5-1-1 medium and never on the gritty mix. They are relatively harmless and are just a nuisance.

@Vladmir I thought that the larvae can damage tender new roots.

They can cause significant damage only in large numbers.

I got them thanks to the garden soil I got and planted my lime tree in. Now they are in the surrounding lemon tree in pots with 511 mix too. Drenched the pots with gnatrol solution. And the 511 I had made was on faster side.

I had little fungus gnats here and there when I started with my plants, but now do not have them. I think as I was learning more about watering habits and soils in containers indoors, I can have more control now over the situation with gnats if they do appear.