So my elderly Uaru female has been getting picked on by what appears to be an Uaru sp. Orange pair. They grew up as a group of 6 oranges and her, but I sold 4 of the oranges because of the bio load. Anyway, after being bullied she stopped eating for a while. I QTed her and rehabbed her, but that made her picky about food, and she wasn't eating any of the usual pellets that the tank gets.
So today I decided to bring out the big guns and brought down some freeze dried krill and frozen krill. The Arowana went to town on it and she ate eagerly like old times.
On a whim, I tested the water for nitrite and nitrate - I had just been doing some filter cleaning and added another one and was curious - and got 0 and 10, respectively. Pretty good for a week since a WC, which I had set up to do tomorrow morning.
Three hours later I came downstairs and my best Satanoperca Leucosticta was dead.
The other fish had slightly elevated breathing, but nothing out of the ordinary for post-feeding. The Arowana was visibly breathing though, and that's usually my clue that the filters aren't keeping up. I tested and the ammonia showed at .25. Maybe that was on its way down... it has been maybe 4 hours at this point. Seems like a classic overfeed, right?
Here's the thing: I didn't overfeed. It was less than the usual amount... just different food.
What do you think is more likely:
1) My recent filter rinse and addition somehow screwed up my BB. (After the rinse the FX5 didn't restart and it took me a few hours and several motor and impeller cleanings to get it going, during some of that time the media was not submerged, though it never dried out.)
2) Frozen krill contains more ammonia than usual
3) Freeze Dried Krill, which was old and hadn't been used in forever, was spoiled and/or contains extra ammonia
4) A bit of freezer burn on the frozen stuff indicates some other chemical reaction that is toxic
5) The fish choked on a giant piece of krill and it wasn't the ammonia at all (though obviously the filters still aren't keeping up)
6) Some combination of the above
I'm at a loss. None of those factors alone should cause this. The tank was clean and in great shape and the fish all healthy. He was the largest and healthiest of the eartheaters, by far.
This really sucks. I've had some stress because of my new discus in another tank, but this tank had been going really well.
So today I decided to bring out the big guns and brought down some freeze dried krill and frozen krill. The Arowana went to town on it and she ate eagerly like old times.
On a whim, I tested the water for nitrite and nitrate - I had just been doing some filter cleaning and added another one and was curious - and got 0 and 10, respectively. Pretty good for a week since a WC, which I had set up to do tomorrow morning.
Three hours later I came downstairs and my best Satanoperca Leucosticta was dead.
The other fish had slightly elevated breathing, but nothing out of the ordinary for post-feeding. The Arowana was visibly breathing though, and that's usually my clue that the filters aren't keeping up. I tested and the ammonia showed at .25. Maybe that was on its way down... it has been maybe 4 hours at this point. Seems like a classic overfeed, right?
Here's the thing: I didn't overfeed. It was less than the usual amount... just different food.
What do you think is more likely:
1) My recent filter rinse and addition somehow screwed up my BB. (After the rinse the FX5 didn't restart and it took me a few hours and several motor and impeller cleanings to get it going, during some of that time the media was not submerged, though it never dried out.)
2) Frozen krill contains more ammonia than usual
3) Freeze Dried Krill, which was old and hadn't been used in forever, was spoiled and/or contains extra ammonia
4) A bit of freezer burn on the frozen stuff indicates some other chemical reaction that is toxic
5) The fish choked on a giant piece of krill and it wasn't the ammonia at all (though obviously the filters still aren't keeping up)
6) Some combination of the above
I'm at a loss. None of those factors alone should cause this. The tank was clean and in great shape and the fish all healthy. He was the largest and healthiest of the eartheaters, by far.
This really sucks. I've had some stress because of my new discus in another tank, but this tank had been going really well.
. I think it was something else - 0.25 ammonia is not going to kill your fish within 3 hours.
and I always toss them in tanks of my adult fish (Amphilophus species) with no apparent negative reaction. But these possible causes to your Uaru has me now thinking twice about this. Any exeriences here? (Sorry OP if this becomes a derail, but I believe its on point with your question.)