Hi John –
Gnat Nix is placed on top of the soil creating a physical barrier that fungus gnats cannot penetrate. Beneficial Nematodes live in the soil and will attack most pest larvae found there. The two products are very compatible when used together and will reduce your fungus gnat problems considerably. Other things to consider…
Gnatnix is made from 100% recycled glass. It is non-toxic and long-lasting. For control of fungus gnats, add a 1/2-3/4 inch layer on top of your growing media — make sure to cover the entire soil surface. This physical control will limit larvae mobility and reduces the appeal for females to lay eggs on the surface. One single application will effectively reduce plant damage.
Happy gardening!