adding tangs in 90gal mixed reef
 

I have a yellow tang(3inch), six line wrass(2inch) and gold banded crown(2inch) in my 90gal mixed reef tank, and would like to add a purple tang or powder brown or both. Im pretty sure my yellow tang will chase them. Do you think is that gonna be a problem? I need your opinion.
Thanks

Build an isolation box out of eggcrate and zap straps. Place box inside the tank and add the new tang. The old fish will spend the next few days getting all excited at the sight, smell, etc. of the new fish but not be able to touch it. When everyone is calmed down, you can release the new tang. I've used this many times in the past and plan to do so again next week.

Also, add a mirror against the tank and try turning off the lights for a bit. These tend to distract or calm down the agitated original inhabitants. I also tend to feed extra.

Anthony

Great idea! I have used the mirror trick and it works but as soon as I took the mirror off they would fight. I put it on and off over the first couple days to calm everything down and by the third day I completely removed it and they still fought for a couple more days but eventualy they got along. I was adding my 4th tang and and the other 3 were not happy lol.

They're same body shapes so I can see some fighting to possible death. Plus all 3 might be a little tight for space in a 90G.

That's good idea. How big is the box and how many mirror, each side?

Yes, I am expecting 3 tangs are tight in my tank. I just can't make up my mind which one. I never thought about purple tang before but they are a half price at our LFS.

Two tangs max. I would say in your size tank (hope you plan an upgrade).

The box I would build would be at least 1' x 1' x 2' in order to fit into your 90g. A bit bigger would be better.

Go with Purple. Powder anything tangs are terrible ick-magnets. The stress will likely cause a big outbreak that will kill at least the Powder Brown.

Same shape yes, but the isolation chamber worked for me to get a school of 6 YTs in my old tank years ago, one at a time.

All I can say is that I had a yellow tang and a powder brown tang in one of my nineties for two years, only to come home one eavening from work to find the brown dead on the bottom, and the yellow died a few days later.
They tore each other up quite badly.
I'd never seen the aggression in that two years, and after it happened, I had plenty of "I told you so"s from other hobbyists.

OK, thanks for your info. I will go for purple tang. However, I'm thinking to do a little bit rock work change before Xmas. Do you think I can keep a baby purple tang in temporally 20gal SPS tank for few weeks? I only have a 3inch lawnmower blenny in that tank.

If there is much of a size difference, especially with the new tang being much smaller than the old one, that can be a recipe for disaster. Much safer IME if the new tang is bigger (i.e. tougher) since the old tang will have home tank advantage, so to speak.

Well, purple tang I see at LFS are about 2.5 inch and my yellow tang is little bit bigger than 3 inch. That why I am thinking to put Purple Tang in 20 gal for few week and change rock work in my 90.

+1 for the purple, they are very shy and your yellow will be the dominant one and like other have said, I'd stick to just those two

I have to agree with nickguay that the YT are dominant. My YT use to attack my blonde naso tang whenever it got to the end of the 120g tank when the YT likes to spend most of its time.

I think this is a recipe for disaster no matter what tang you get or how big it is. You have a resident yellow tang in at most a 4 foot long tank. By now it think it owns that tank. There's no amount of rock work rearranging you could do in such small of a space for it to think it wasn't its tank.

Purple tangs are the same genus, with a nearly identical body shape. I would be shocked if within moments of adding the purple to your tank one of them wasn't seriously injured. At the very least you're going to be dealing with constant, mid-level aggression between the two, with the dominant one keeping the subordinate one in a near constant state of stress.

I've tried to do what you're doing in 90 gallon tank. It didn't matter what species, or what genus, Zebrasomas were utterly intolerant of another tang in a tank that size. There might be people on here who've gotten away with it for a time, but the chances are good this is not going to work long term.