Overall, a 55 is still a tank for nano fish imo
. A large fish like a foxface just can't thrive in one. It will also cause you issues down the road. Big fish, big poop!
Also, mandarin is something to think about months down the road. My 55 has been up for some time and I have a mandarin in there. I literally pump the tank full of pods
. I like a challenge and throw money at my problems...so I have a mandarin.
One of my favorite fish in my 55 is an indigo dottyback. It's a hybrid fish from an orchid and striped dottyback. Really cool fish. Check it out. Removing the foxface will also open the tank up some more for a couple other smaller fish that will make the tank more lively.