Shy Guppy with Outgoing Goldfish

[TheBeth23]

I have a fair fish, a common Goldfish named Spot and a loach named Whiskers. I’ve had them for about 6 months and they are doing great. Both are very outgoing, always happily swimming and not hand shy. I recently received a male guppy(unnamed). He is healthy and eats great, but he is very shy. His tank mates are larger but friendly towards him. There’s no nipping or chasing, and meal time goes great. There is no fighting for resources and I have a gentle flow filter. He hides in the back towards the top mostly(sometimes the bottom). I’ve never had guppies but I read they like to hang in groups, but also males can be territorial. What should I do that doesn’t include separating? Should I try a male mate or 2? Also, what should I name him?

 

[Colin_T]

put some floating plants like Water Sprite in the tank

 

[GaryE]

The top corner is the hiding place of last resort. When a fish goes there, it is stressed and afraid. It wants to get away, and that's as far as the glass will let him go. He's in with bigger fish, and as the goldfish grows, it will probably eat him. He likely senses that.
The solution is another tank, either yours if you add one for him, or someone else's if you rehome him.