Plant health. Can anyone tell me how to fix this. And also how to exterminate gnats.
Those godless pests! Depending on how bad the infestation is you can try a few things. Indoors you can get away with sticky strips and that usually will clean up an issue in an enclosed area like a tent. If you are outdoors then you need to take more drastic action. Ladybugs which you can buy online are a great natural option, or you can try neam oil spray but I would read more about that option.