I finally got the nitrogen cycle down even though I went through it with my Betta it seemed to differ from my ten gallon tank and have even set up a 55 gallon coming soon. I got the gold fish out of my ten and now I have zebra danios and I recently got four guppies. The guppies are hiding in the corner which I read the stress is normal, however I noticed my danios are picking on one of the guppies and he is terrorized in the corner afraid of them. They are supposed to get along but it looks like they are a little aggressive should I be worried? I'm sorry if the pictures don't help it's just the one in the corner staring at the glass....