Firefish behaving abnormally

KC V. · Dec 11, 2018

Hello there.

I've tried scouring the forums to see what I can find that has already been posted, and I'm a little stuck about what this could be. I have a fairly new tank (been up 25 days--cycled following Dr. Tim's instructions), and I added two firefish who seem to be paired at the LFS because the tank had stabilized for two weeks. These buds have been inseparable their first few days in the tank, but now one of the firefish has been behaving very oddly (hanging out in the sand away from the rock, or chilling on the back wall of the tank). Occasionally he'll move from one corner of the tank to another. I've attached a picture of this guy.

Breathing is normal. Responds to food and swims normally all other times. Onset was very rapid, while I was gone at work. The other firefish is happy as can be. Stats are NH3 = 0ppm, NO2 = 0ppm, NO3 = 7 ppm, pH = 8.1, salinity = 1.0245. Since adding fish, only NO3 has moved. Any ideas or experience with this situation? Should I wait and see a bit longer, or move to QT and treat? Many thanks!

cracker · Dec 11, 2018

Sorry I can't help Ya much . As well you know, keep an eye on it .
here is a bump for You

Big G · Dec 11, 2018

How big is the tank? Purple Firefish do not get along well with similar shaped fish and/or conspecifics. You can occasionally keep pairs but it can be real hit and miss, especially as it is difficult to tell the difference between males and females. Consider rehoming the fish that is having difficulty in the tank. The fish will decline slowly and be subject to poor health. Sorry.

GoldeneyeRet · Dec 11, 2018

He looks thin...

Could be a parasite but I suspected not eating due to intimidation from the other firefish. Firefish dont get along unless a true mated pair, which is not easy to get.

KC V. · Dec 11, 2018

Big G said:
How big is the tank? Purple Firefish do not get along well with similar shaped fish and/or conspecifics. You can occasionally keep pairs but it can be real hit and miss, especially as it is difficult to tell the difference between males and females. Consider rehoming the fish that is having difficulty in the tank. The fish will decline slowly and be subject to poor health. Sorry.

Display part is 35-40G.(it's an AOI 45G)

No worries. I was concerned a bit about that, but the LFS did a good job at convincing me the pair was mated and got along (which they seemed to at first). But yeah, I will separate them and then that will have to do.

KC V. · Dec 18, 2018

Thank you, all, for your help with this. Unfortunately it seems that due to the rapid onset of symptoms this little guy was beat up by his tank companion. I separated them, but the stress was too much for this little guy so he succumbed shortly after being moved to a different temporary tank. I'm keeping a close eye out for any [potential] disease, just in case at this point.