I have three sets of cories. Two "3 lined", 5 Elegans, and 6 pandas. Just lost an Elegans.
I have had real trouble with my tanks. Now, finally, I am fully cycled.
Last weekend, everything went to poop. Tank got scum on top, turned very cloudy, and begin to stink. Even though heavily planted, it had never cycled. As I learned after the fact.
Changed my water flow, surface scum went away, and water started clearing, and started getting NO2 readings, for the first time on Monday. Yesterday, after a rise of NO2 all week and then a drop on Thursday, it subsided to 0 along with 0 NH3. I have about 20 PPM of NO3.
From the beginning the Elegans would charge the surface, break the surface, and return to depth. As far as I know, this was normal. Actually all the cories did this, not just the Elegans.
About the time, last Monday, when everything started happening, one of the Elegans would periodically, go into the extremely active spirals, appeared out of control. He (or she) would then slowly sink to the bottom. The first time I witnessed this, I figured it was dead, but before I could do anything, it righted itself and moved on, appearing normal.
I "ass/u/me" I witnessed the same Elegans do this several times each day. Sometimes it would lodge in a plant, nose down, whatever, but always within several minutes, it would move on, as if nothing had happened.
Yesterday, I noticed one of these spasms and the fish landed on a sandy spot in front of aquarium, on its side. I went about my business, but noticed it still there many minutes later. Its gills were moving slowly. I gave it a nudge and it moved off, normally, but within 15 minutes or so, I noticed it in about the same place. Finally it appeared to stop breathing and died.
All of my fish are troopers; they have been through a lot. Anyone know about this type of actions. From the first time I saw it I did not think it was natural...just too fast, and too erratic. Any opinions if the rest of these guys will go this route? Is this a result of the delayed cycling and NH3 or NO2 poisoning? Any insight appreciated greatly. Thanks.