Gnats or Thrips...Sand???

So...does anyone have personal experience with putting sand on top of your soil to prevent thrips or gnats from reproducing? Just want to make sure before I throw sand on my grow.
Thank you!

These worked better for me than sand....Pretty cheap.

2 waterings and all were gone.....Sticky traps for those flying around.

Soak dunks overnight in water jugs.

sweet, they didn't do anything to your babes?

Nope...The active ingredient is made from Chrysanthymum flowers.....Plants didnt even notice it....Probably thanked me for it.

You can also add them to your res in hydro if you have them in your dwc.

awesome. thank you for your help.

BSI, you may accept a +rep from time to time, but last january, when you made that post, was not the time... i'd just like to clear up a minor discrepancy, i.e., that the active ingredient in mosuito dunks is NOT made from chrysantemums (i think you are referring to the pyrethrin insecticides) but it is bacillus thuringiensis, a bacterium that is toxic to the larvae of some species of insects. it seems to be effective against fungus gnats although not sure how effective it is against thrips. couldn't hurt to try, however. good luck...