[QUOTE="CPC, post: 7368191,So my question is do I get one ore two more tangs? And is my choice of yellow and yellow eye Kole good options? If blue goes back to the 55 is it a pretty good chance the yellow, brown and Kole will get along?
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Welcome. You've come to the right place.
But, you are in a tough spot. Powder blue and powder brown tangs aren't great choices for the tanks you have. They individually should have a 6 foot tank, and I wouldn't combine them unless I had a very large tank.
A 55 isn't a good permanent home for any of the tang species. A 90 can work, but I would recommend only one tang there, and the 2 species you have aren't good choices for a 90 gallon. The best choices for a 90 would be: kole, tomini, white tail. Okay choices would be: yellow, purple, scopas. Again, I would recommend only 1.