Is this aggression normal (cardinalfish vs wrasse)?

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Petrichor

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Hey all, I'm not sure if my fish are having aggression issues or if this is normal behaviour. Any advice is appreciated!

I recently downsized from a 24g to a Fluval 13.5. In it I have plenty of live rock with many crevices, tunnels, and hideyholes, my corals (mostly small except for a "large" toadstool), and two fish: a pajama cardinalfish and six-line wrasse. They were together in my 24g tank for about 2 years, however that tank was in a different, in-frequented room so I can't tell if this is "normal" behaviour for the two.

The PJ spends his time in the more open sections of the tank. I have noticed that he seems to antagonize the wrasse by charging and nipping (?) at the wrasse. He does this often enough that it almost looks like he's actively waiting/searching for the wrasse. The wrasse, in response, will either dart off into the rockwork or flair up and turn sideways while standing his ground. Occasionally the wrasse will make several "pecks" at the PJ after being charged. These pecks don't seem to make physical contact with the PJ, who appears unfazed by this. I don't believe I have seen the wrasse initiate any charges at the PJ.

So far they've been together about 2-3 weeks. I have not seen any physical damage on either fish (sores, ripped fins, etc), and both are eating well. The PJ sometimes shows food aggression, but I've been spreading out their food a bit more and that is helping.


I guess I just need reassurance that it's in my best interest to get rid of the PJ. I'm reluctant to do so as he was my first fish, however the wrasse is by far my more favorite species, so I don't want to choose between the two. :(
 
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Petrichor

Petrichor

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Bit small of tank for mature PJ but workable. Way too small for sixline wrasse let alone moving from larger to smaller with company. I'd keep the PJ and lose the wrasse, long term that's not a good fit.
Genuinely asking (not arguing so please don't read this the wrong way), but why remove the wrasse when the PJ seems to be more space aggressive?

I know six-lines are recommended for larger tanks, however I've read many testimonials that state they're fine in nanotanks down to 10g. I've also read some six-lines can get too aggressive in small tanks, so it honestly seems like a 50/50 split on whether or not six-lines are nano compatible and depends on the individual fish.
 

Quietman

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No worries...Six Line wrasses are much more active fish and while they may survive in smaller tanks I do not think it's the optimum environment for them. There are smaller wrasses Pink Streaked and Possum that do very well in nano tanks.

Whereas PJ's even though approx same size are much more sedate in normal behavior.

I've never been a huge proponent of the viewpoint that an individual fish can be much/any different from the species. Fish species have very well documented patterns of behavior. The only exception maybe what the hobby is doing with captive bred (which I'm all in favor of and support in purchasing) where specific characteristics/behavior can be bred into the species over time.

Sometimes we don't have a choice and life forces us to do the 'less than optimal' for our pets. But if you have an outlet for the wrasse, I'd consider it. For example, I sold off a Yellow Watchman Goby rather than put him in a 5 gallon pico - although I'd have no issues putting my Yasha Goby in there even though the recommendation is 10 gallon.

I'm not one of those fish keepers that are terribly strict about aquarium size recommendations with my fish but looking at the character and behavior of the fish there is a reasonableness I try to follow.
 
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Petrichor

Petrichor

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No worries...Six Line wrasses are much more active fish and while they may survive in smaller tanks I do not think it's the optimum environment for them. There are smaller wrasses Pink Streaked and Possum that do very well in nano tanks.

Whereas PJ's even though approx same size are much more sedate in normal behavior.

I've never been a huge proponent of the viewpoint that an individual fish can be much/any different from the species. Fish species have very well documented patterns of behavior. The only exception maybe what the hobby is doing with captive bred (which I'm all in favor of and support in purchasing) where specific characteristics/behavior can be bred into the species over time.

Sometimes we don't have a choice and life forces us to do the 'less than optimal' for our pets. But if you have an outlet for the wrasse, I'd consider it. For example, I sold off a Yellow Watchman Goby rather than put him in a 5 gallon pico - although I'd have no issues putting my Yasha Goby in there even though the recommendation is 10 gallon.

I'm not one of those fish keepers that are terribly strict about aquarium size recommendations with my fish but looking at the character and behavior of the fish there is a reasonableness I try to follow.
That is very true, it's important to think about what's best for the fish and not just what I as the keeper want. Thanks for reminding me of that. There are plenty of options for me in terms of nanofish, so I'll start researching what's in my area (Canada has less selection, unfortunately) and then figure out rehoming one or both.
 
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bnord

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Looks like you indeed have your hands full, guess it is which you enjoy more will win, but I have had 4 six liners, and 2 were perfect mates and 3 were horrible tank mate regardless of the space allowed And were not relaxing for anyone, especially me
 
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