Random Tang aggression

[LFGJP]

I’ve had my tank (210g) set up for about 2 years now
I have multiple tangs including purple, blonde naso, hippo, and powder blue. I’ve done some research and added them in order so I could minimize the aggression.

I thought I was successful here until yesterday, randomly I noticed that the hippo was getting aggressive with the blonde naso to the point where the naso won’t come out of its hiding spot.

It comes out to feed, then the hippo just gets so aggressive it just darts back after it eats.
It’s similar size, no other aggression issue.
I feed the tank well
They have been getting along just fine for about a year and half now.

Anyone knows what causes this? Also is my only option to take one of them out of the tank?

 

[boacvh]

I've had a few episodes like that where after years of nothing suddenly one was aggresive. Never got rid of anyone. The mirrors helped me. I put several around the tank

 

[LFGJP]

I've had a few episodes like that where after years of nothing suddenly one was aggresive. Never got rid of anyone. The mirrors helped me. I put several around the tank

Where did you place them?

 

[boacvh]

On the glass. I purchased a few cosmetic hand held mirors and taped them to the glass on the outside

 

[LFGJP]

On the glass. I purchased a few cosmetic hand held mirors and taped them to the glass on the outside

I’ll definitely try that
I don’t know why it’s just going after one, but at least the others are getting along just fine

 

[Largeangels]

Tang aggression can by dynamic so always have a backup plan to remove the offender. Fine one day, then someone decides they don't like a certain fish and it can be like WWIII.

 

[LFGJP]

On the glass. I purchased a few cosmetic hand held mirors and taped them to the glass on the outside

Worked like a charm! Thank you so much for the advice!

 

[boacvh]

Worked like a charm! Thank you so much for the advice!

Great to hear. It has worked wonders for me. In my experience it comes and goes.