I've had these 5 ablino corys for about 5 or 6 weeks now. They were one of the first fish I introduced to my tank when it first finished cycling, along with some neon tetras.
A couple of weeks ago, I noticed one of my corys, just one, was staying at the top of the water, and even floating vertically against the glass at times. When watching his behavior, it looked like he was unable to descend. After a day of fasting, and a reduced water level in the tank, he was fine for a couple more weeks.
Fast forward to this weekend, and he's doing it again. At least I think it's the same one. It's hard to tell the corys apart. He just stays at the top of the water, acting like he's unable to descend, and sometimes floating vertically (head up, tail down) against the glass.
Because he looks like he can't descend, I'm concerned he can't eat. This cory, unlike the others, is easy to catch in a net. I put him a breeder box, and he's okay. No more floating. But he doesn't eat in the breeder box. It's like, since he's closer to the surface, he isn't struggling to breathe, but like I said, no interest in food in the box.
I have not noticed any other symptoms. No redness around the gills. No worms sticking out of his anus. No discoloration. No white fuzzy areas. No sand-like white spots. His barbells are in tact. No rot or damage to his fins.
What changed in my tank recently:
1. It's been a week now since I introduced the betta sorority to the tank
2. I switched from Top Fin water conditioner to Prime
3. I started filling my tank a little more, because the water level was too low for the filter to recover from a power outage
Water is reading 0 ammonia and 0 nitrites. Cycle is in tact.
I did try reducing my water level again, but that didn't help. And although ammonia and nitrites are reading 0, a lot of things I've read have said this behavior can be symptomatic of water issues, so I changed the water every day for the last 3 days.
This tank is slightly taller than a standard 30 gallon, as if it is actually a reptile tank.
I have a few thoughts on what could be causing this and what to do about this, and I'd like to hear from you all.
1: Possible Swim Bladder condition - Isolate and treat
2: My Tank is too deep for this guy - I have considered getting a suction-cup reptile island, and putting it a few inches below the water's surface, as a more shallow surface for the corys to chill out on, but that would have to wait for payday.
3: My tank could be over-crowded. It's at 90% stocking level, according to aquadvisor, but 3 of the species in the tank are bottom feeders. In addition to the 5 female bettas and dozen neon tetras, there's 5 corys, 6 kuhli loaches, and a handful of ghost shrimp.
4: Other illness I haven't considered
The other 4 corys do not exhibit the same symptoms, although there is one other cory that hangs out at the top of the water with this one... but it appears to be by choice. This other cory can indeed descend, and I when I put the affected cory in the breeder, this one descended to the substrate and started basking with the other 3.
I did try catching all 5 corys, as I was going to try moving them to my 10 gallon to see if that helped, and I was able to catch 4 of them, but the 5th one was too good at evading me. So they didn't get moved to the 10 gallon. I freed them back into the 30 gallon. If I'm going to move them, I want to move all of them, not all but one.
Any advice, guys? Should I expect this cory to die? Should I keep him isolated in the breeder box? I don't have a quarantine tank right now. Should I just free him back into the tank and wait for this to pass? Does he sound sick, or does this sound like normal corydora behavior? Could he just have overeaten, and will resume swimming normally after he digests his food?
A couple of weeks ago, I noticed one of my corys, just one, was staying at the top of the water, and even floating vertically against the glass at times. When watching his behavior, it looked like he was unable to descend. After a day of fasting, and a reduced water level in the tank, he was fine for a couple more weeks.
Fast forward to this weekend, and he's doing it again. At least I think it's the same one. It's hard to tell the corys apart. He just stays at the top of the water, acting like he's unable to descend, and sometimes floating vertically (head up, tail down) against the glass.
Because he looks like he can't descend, I'm concerned he can't eat. This cory, unlike the others, is easy to catch in a net. I put him a breeder box, and he's okay. No more floating. But he doesn't eat in the breeder box. It's like, since he's closer to the surface, he isn't struggling to breathe, but like I said, no interest in food in the box.
I have not noticed any other symptoms. No redness around the gills. No worms sticking out of his anus. No discoloration. No white fuzzy areas. No sand-like white spots. His barbells are in tact. No rot or damage to his fins.
What changed in my tank recently:
1. It's been a week now since I introduced the betta sorority to the tank
2. I switched from Top Fin water conditioner to Prime
3. I started filling my tank a little more, because the water level was too low for the filter to recover from a power outage
Water is reading 0 ammonia and 0 nitrites. Cycle is in tact.
I did try reducing my water level again, but that didn't help. And although ammonia and nitrites are reading 0, a lot of things I've read have said this behavior can be symptomatic of water issues, so I changed the water every day for the last 3 days.
This tank is slightly taller than a standard 30 gallon, as if it is actually a reptile tank.
I have a few thoughts on what could be causing this and what to do about this, and I'd like to hear from you all.
1: Possible Swim Bladder condition - Isolate and treat
2: My Tank is too deep for this guy - I have considered getting a suction-cup reptile island, and putting it a few inches below the water's surface, as a more shallow surface for the corys to chill out on, but that would have to wait for payday.
3: My tank could be over-crowded. It's at 90% stocking level, according to aquadvisor, but 3 of the species in the tank are bottom feeders. In addition to the 5 female bettas and dozen neon tetras, there's 5 corys, 6 kuhli loaches, and a handful of ghost shrimp.
4: Other illness I haven't considered
The other 4 corys do not exhibit the same symptoms, although there is one other cory that hangs out at the top of the water with this one... but it appears to be by choice. This other cory can indeed descend, and I when I put the affected cory in the breeder, this one descended to the substrate and started basking with the other 3.
I did try catching all 5 corys, as I was going to try moving them to my 10 gallon to see if that helped, and I was able to catch 4 of them, but the 5th one was too good at evading me. So they didn't get moved to the 10 gallon. I freed them back into the 30 gallon. If I'm going to move them, I want to move all of them, not all but one.
Any advice, guys? Should I expect this cory to die? Should I keep him isolated in the breeder box? I don't have a quarantine tank right now. Should I just free him back into the tank and wait for this to pass? Does he sound sick, or does this sound like normal corydora behavior? Could he just have overeaten, and will resume swimming normally after he digests his food?
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