I would get him neutered, I did this with my Apollo and he is SO much happier. I have a post of my pets on here under my fuzzy ( or is it furry? ) family

Just an idea ... I had two boys and both got through their neuters wonderfully
Unfortunately everywhere has rats from Petco to BYB's on craigslist

And most are horribly neglected ... Not to mention stores that sell them as feeders