it's my second year growing tomatoes and this year i have two better boy plants and one brandywine. i noticed some leaf curl on the brandywine and under the leaf there were tiny black bugs. i don't have any pictures but they looked just like gnats, though maybe a touch smaller. i sprayed them and killed most of them but found more a few days later and a few on one of my better boy plants. they don't seem to be doing too much damage other than curling the leaves. i just want to know what they are and what to expect from them. anyone familiar w/ them?