Two clown gobies 1 tank?

[Njane89]

I was wondering if you can keep two clown gobies in the same tank?

I have a 20 gal with one yellow clown goby, tailspot blenny, and a small orange diamond goby/tiger pistol pair. I saw that oceans had some green clown gobies and I would love one in my tank!! Just want to make sure it will be ok first.