I have a little terrarium. I used to have a camellia sinensis plant for tea, but i got rid of it because seemingly everytime It grew some new growth, the new growth would brown from the tip back. Always. I thought it was a disease called die back which happens with camellias. But maybe it wasn't. My lemon seedling has two leaves like this, but they haven't dyed all the way back. And my guava has about 4 leaves doing it on the tips. One just fell off. This is really bothering me. But now I see all these little tiny tiny white bugs that just crawl around. Any ideas what they would be?They're too small to photograph. So what's wrong with my plants?