Fish agression

[aechild]

I have a 75 gallon with a medium size sailfin tang, today I purchased a small Niger trigger. When I first put the trigger in the tank he went straight to my cleaner shrimp and the tang went after him. The trigger hid and ever one calmed down. About 3 hours went by and the trigger came out of hiding and was swimming. They both have chilled out unless one tries to be near the cleaner shrimp then they chase each other. Will adding a second cleaner help and also my sail fin has 2 nips in his dorsal now will they heal back to normal?

[Betta132]

Both of those fish are too large for that tank, especially the tang. A sailfin needs at least a 180g tank, because they need long tanks in order to swim back and forth in long, uninterrupted lines. The trigger just needs space.

[bleumoon]

I don't think adding another shrimp will help. Maybe the sailfin is just claiming his territory and showing his dominance.

Check out http://www.liveaquaria.com/product/aquarium-fish-supplies.cfm?c=15 for researching the fish before you buy them. Those fish get freggin huge man. If you want you could see if your lfs would swap them out for smaller fish.

[Betta132]

A sailfin, if not stunted, will grow to eight inches long and about that high, and they're VERY ACTIVE. You need to remove both or immediately upgrade to a 180g, that will solve your problem.

[JoelA7]

Without diminishing the veracity of above responses regarding the size aquarium needed for a sailfin tang or Niger trigger while small the two should get along ok. Whether the niger goes after the shrimp is another story. If you feed well, and you should, you'll get a lot of growth from your tang and trigger and need a much larger tank. Btw-they get more and more beautiful as they mature.

[jjk_reef00]

Not really sure why you are surprised at this outcome. Tangs are known to be territorial especially in undersized tanks. And triggers will stand up for themselves. If you are lucky they will cool out a co-exist for a little while but it is only a matter of time before one stresses to death. On the other hand it is a very real possibility that they continue beating on eachother... I'd return one or both fish and get fish more appropriate for your aquarium size. Please research before you purchase, this is a good thread:
http://www.reefcentral.com/forums/showthread.php?t=2068112&page=540