Today I called my local hydro store & told him about the gnat problem. He suggested that I could try to put a thin layer of sand to suffocate the gnats. Just for the record I went out to Home Depot & bought a bag of sand. I added a thin layer of it on 2 of small veg plants & then I thought hold up wait lets go to the forum & see what the pros say about this.
There you have it.
There you have it.