Distressed Cories

[Aquastrategist]

Hi, I have a 50 gallon planted tank including 5 cories. All 5 have been huddled together behind this driftwood peice a lot in the past couple days.
Ive been feeding them property, the temp is 78 and all other fish are fine. I have otos, angels, neons and rainbows. The ph is 7.6 which I know is high for them but the other fish are fine. They seem to be breathing extremely quickly.

 

[Sharpchick]

Have you checked your nitrate levels? In my experience, cories are real susceptible to increased nitrate levels. If you're doing your water tests, even on a cycled tank, you have to check more than ammonia and pH...

 

[Rlavassor86]

Yea corys are really sensitive to nitrate. Also what substrate do you have? If its too sharp it can injure them.

 

[Aquastrategist]

Sand and gravel. I also test everything, including nitrates. My nitrites and nitrates are...
-nitrate 20
-nitrite 0

 

[Sharpchick]

Sand and gravel. I also test everything, including nitrates. My nitrites and nitrates are...
-nitrate 20
-nitrite 0

Do a water change. Cory breeders usually do not let nitrates get above 10.

Some people recommend baths in pure chlorophyll - 4 cups of tank water to 1 ounce of liquid chlorophyll in a large container for 10-15 minutes. Three times a day for 7 days.

They are certainly in nitrate shock, possibly nitrate poisoning. If they start bending, you'll know it's nitrate poisoning.

But you don't want to let it get there. Get your nitrates down as low as possible. Do a water change, and if you have some Amquel or Prime, add that per directions on the bottle.

 

[Hobgob]

20 ppm would not cause nitrate positioning. But it is time for a water change. Normally people don't allow the nitrate to get much more above 20ppm but some people say 40ppm. I personally wouldn't let it get to high above 20ppm. But your fish are most likely fin. Do they have a lot of hiding spots or just that one?

 

[Sharpchick]

20 ppm would not cause nitrate positioning. But it is time for a water change. Normally people don't allow the nitrate to get much more above 20ppm but some people say 40ppm. I personally wouldn't let it get to high above 20ppm. But your fish are most likely fin. Do they have a lot of hiding spots or just that one?

With all due respect, some fish - like cories, fancy goldfish and bettas, to name a few - are much more sensitive to nitrates than others.

If the cories haven't started curling up yet, then it's most likely nitrate shock.

I know wherefore I speak on this one. I noticed the behavior described by the OP with four cories of mine in a mixed 40 gallon tropical tank. I tested for ammonia (0), nitrite (0), nitrates (10), pH 7.2, and figured nothing to be worried about - I'd do my water change on schedule the next day.

When I got home from work was when I saw the curling. Still, no other fish in the tank seemed affected or acting strangely in any way. I tested, and couldn't decide whether the color on the nitrate chart was 10 or 20 ppm, or somewhere in between.

Even after the water change, the cories were listless and not eating. They started dying that night, one and two at a time.

That was when I learned two real important lessons after six or seven years of fish keeping.

Even when you have a cycled tank, you always test ammonia, nitrite, nitrate and pH.

And second, what all the message boards and blogs about cories say are right - they are real sensitive to nitrate. My LFS had warned me about that when I bought them.

 

[Brandon4432]

Corys are extremely sensitive towards salt

 

[Hobgob]

With all due respect, some fish - like cories, fancy goldfish and bettas, to name a few - are much more sensitive to nitrates than others.

If the cories haven't started curling up yet, then it's most likely nitrate shock.

I know wherefore I speak on this one. I noticed the behavior described by the OP with four cories of mine in a mixed 40 gallon tropical tank. I tested for ammonia (0), nitrite (0), nitrates (10), pH 7.2, and figured nothing to be worried about - I'd do my water change on schedule the next day.

When I got home from work was when I saw the curling. Still, no other fish in the tank seemed affected or acting strangely in any way. I tested, and couldn't decide whether the color on the nitrate chart was 10 or 20 ppm, or somewhere in between.

Even after the water change, the cories were listless and not eating. They started dying that night, one and two at a time.

That was when I learned two real important lessons after six or seven years of fish keeping.

Even when you have a cycled tank, you always test ammonia, nitrite, nitrate and pH.

And second, what all the message boards and blogs about cories say are right - they are real sensitive to nitrate. My LFS had warned me about that when I bought them.

Considering that I have 5 sturbai in a grow out tank with 150 baby bristle nose pleco and my nitrate levels are at 30 ppm for my water change and still is and have no issues or ever have. And no you do not need to test all your levels. When your tank is established and you have a good understanding of what going on in the tank. Lots of people on here haven't tested their nitrate levels in a long time. The last time someone asked how often to test I believe mfdrookie said he lost his nitrate test. Your nitrates levels should always be roughly the same at the end of the week of you are feeding and doing tank maintanace properly. And salt was fine with my Cories. I used 1tablespoon per 10gal and checked to make sure the had no buoyancy problems. Normally people use 1 tbsp per 5 gallons but I wouldn't do it at first.

 

[Sharpchick]

Considering that I have 5 sturbai in a grow out tank with 150 baby bristle nose pleco and my nitrate levels are at 30 ppm for my water change and still is and have no issues or ever have. And no you do not need to test all your levels. When your tank is established and you have a good understanding of what going on in the tank. Lots of people on here haven't tested their nitrate levels in a long time. The last time someone asked how often to test I believe mfdrookie said he lost his nitrate test. Your nitrates levels should always be roughly the same at the end of the week of you are feeding and doing tank maintanace properly. And salt was fine with my Cories. I used 1tablespoon per 10gal and checked to make sure the had no buoyancy problems. Normally people use 1 tbsp per 5 gallons but I wouldn't do it at first.

I wouldn't be happy with constant nitrate levels at 30 ppm for any fish. That's usually a sign of overstocking.

But your tanks are your tanks.

 

[Hobgob]

I wouldn't be happy with constant nitrate levels at 30 ppm for any fish. That's usually a sign of overstocking.

But your tanks are your tanks.

yes it is normally a sign of overstocking.
Did you not read that there is a bunch of fry in the tank lol. I have like 150 babies bristlenose plecos in that tank growing out. In my opinion that's not overstocking when the tank is a grow out. I use to do a water change everyother day on the tank.

 

[Hobgob]

And yes my 35 with Breeding pleco's. 20g with breeding gbr's, 30 with breeding kribs. My two Betta tanks for spawning them. My 110g display with another pair of breeding kribs and all my grow out tubs are my tanks. Maybe the fish will be yours one day.

 

[Sharpchick]

yes it is normally a sign of overstocking.
Did you not read that there is a bunch of fry in the tank lol. I have like 150 babies bristlenose plecos in that tank growing out. In my opinion that's not overstocking when the tank is a grow out. I use to do a water change everyother day on the tank.

Yes, I read about the BN fry. I didn't comment about that because if you and I were, say...having coffee and you'd told me that, I'd have had a bunch more questions.

That have nothing to do with this thread, so I didn't see the point in hijacking it.

 

[Aquastrategist]

I think they could just use more space to hide, ill do a rescape later.