Albino Corydora swimming erratically

Tank
What is the water volume of the tank? 29 gallons
How long has the tank been running? Over a year and a half although I've changed species since. It had no fish for about a month and a half (Late October 2022-December 2022) but still planted and running filtration/heater. 6 Cardinal Tetra and 4 Albino Corydora were added on December 14, 2022. Then 4 more Cardinal Tetra added on January 13, 2023.
Does it have a filter? Yes. A Fluval 307 canister with a spray bar cut down to fit the tank width.
Does it have a heater? Yes
What is the water temperature? 77.5 F
What is the entire stocking of this tank? (Please list all fish and inverts.) 10 Cardinal Tetra, 4 Albino Corydora, and numerous live plants. Sand substrate.

Maintenance
How often do you change the water? every 6-9 days depending on how it looks and my schedule.
How much of the water do you change? about 10 gallons
What do you use to treat your water? seachem prime
Do you vacuum the substrate or just the water? I vacuum the substrate with a siphon

*Parameters - Very Important
Did you cycle your tank before adding fish? Yes
What do you use to test the water? API Master test kit
What are your parameters? We need to know the exact numbers, not just “fine” or “safe”.
Ammonia: 0
Nitrite: 0
Nitrate: 0
pH: 8.2

Feeding
How often do you feed your fish? once daily
How much do you feed your fish? a pinch of tropical slow sinking micro pellets for the tetra and 3-4 sinking pellets for the corydora
What brand of food do you feed your fish? Ultra Fresh (micro pellets) and Aquatic Arts (sinking pellets)
Do you feed frozen? no
Do you feed freeze-dried foods? no

Illness & Symptoms
How long have you had this fish? December 14, 2022
How long ago did you first notice these symptoms? This morning
In a few words, can you explain the symptoms? swimming erratically
Have you started any treatment for the illness? Not yet
Was your fish physically ill or injured upon purchase? No
How has its behavior and appearance changed, if at all? It is swimming erratically and appears to be breathing more quickly than normal. It is also the smallest of my four corydora. They are all the same age and purchased on the same day.

Explain your emergency situation in detail.
(Please give a clear explanation of what is going on, include details from the beginning of the illness leading up to now)

Today I was adding some new plants and I noticed one of the corydora lying on its side at the bottom of the tank. I though at first it might be dead but as I moved my gloved hand closer it swam away. I've been keeping a close eye on it all day now, and it seems to be swimming erratically and once in a while it goes to the surface, taps the surface 3-4 times, and then sinks down (not swimming just free falling) to land on its side at the bottom. It lays there for a bit and then goes back to its normal business.

It does not appear to have any open sores or damage to fins or barbels, although its breathing is a little bit labored. All other fish are acting normally and when I tested the parameters ammonia, nitrite, and nitrate all came back zero.

Include pictures

The corydora in question is currently sitting in the corner with one of his buddies which is not unusual for them. They all congregate in that same corner sometimes. I tried to get some photos of the others but they are a bit blurry because they were swimming.

 

Are you sure the nitrates are 0? Did you test right before a water change? Seems unlikely in a cycled and stocked tank unless you did a huge water change right before testing. I don't see much plant mass, so I don't think they are using all the nitrates.

 

My last water change was on Friday. I did recently add Seachem Renew to the filter instead of Carbon. Could that be why the nitrates are 0? I'll retest in a bit to make sure that was accurate.

 

I don't think you have a nitrate problem, but that reading of 0 got my attention.

Seachem makes a lot of unnecessary products. There is no need for carbon or Renew, which is less effective then carbon at removing organics.

Why are you using those products?

pH8.2 is pretty high for a Cory. They can live in that water, but may not thrive in it. Same for the Cardinals.

It possible that it is a swim bladder problem, where it's laying on bottom, can swim to surface, but then drops bact to the bottom. I recently had a fish with swim bladder issues. Like yours, it layed on bottom breathing heavily and really struggled to reach food at feeding time. He looked pretty bad. I fed him with a turkey baster for a week and he started perking up. After about 3 weeks the swim bladder problem was gone and now he is growing and wanting to mate.

 

Last time I tested my tap water the phosphate was at 2.0 ppm. When I test the phosphate in the tank it consistently hovers around 4.0 ppm despite regular water changes and vacuuming the substrate. I use Prime to condition the water, but it does nothing for phosphate, so I started using Renew to help with it. I decided on Renew instead of Phosguard because it removes other organics besides just phosphate. Should I discontinue the Renew? Would twice weekly water changes maybe be better?

 

Why are you concerned with Phosphates? Are you having bad algae issues? Phosphates will come from the breakdown of organic matter (food, plants, dead anmimals etc.). You can feed less, and vac the substrate more to reduce organics. You can greatly increase plant volume.

I've not used any of these products. My tap phosphates are 1ppm and before a water change the tank phosphates are 1ppm. Maybe adding a lot of plants, especially emergent plants and floaters would be a better way to control the phosphates. Plants with access to air (unlimmited CO2) grow faster and take more nutrients. The neons as well as the corys would appreciate more cover and dimmer light. There is no need for bright light in a low tech tank.

 

I was having bad algae issues. It completely covered my ludwigia and swords. The swords all melted and the ludwigia is still struggling to recover. I also had a very large piece of driftwood in the tank but I removed it because the algae had established on it and no matter how much I scrubbed it with a brush to manually remove it every water change, it would still come back. I’ve added a bunch of plants to fill in the space where the driftwood was and added a few moneywort floaters.

Why are you concerned with Phosphates? Are you having bad algae issues? Phosphates will come from the breakdown of organic matter (food, plants, dead anmimals etc.). You can feed less, and vac the substrate more to reduce organics. You can greatly increase plant volume.

I've not used any of these products. My tap phosphates are 1ppm and before a water change the tank phosphates are 1ppm. Maybe adding a lot of plants, especially emergent plants and floaters would be a better way to control the phosphates. Plants with access to air (unlimmited CO2) grow faster and take more nutrients. The neons as well as the corys would appreciate more cover and dimmer light. There is no need for bright light in a low tech tank.

I just ordered some Golden Pothos from Home Depot and some tubing suction cups from Amazon. I'll add those this week and let you know how it goes!

 

Why are you concerned with Phosphates? Are you having bad algae issues? Phosphates will come from the breakdown of organic matter (food, plants, dead anmimals etc.). You can feed less, and vac the substrate more to reduce organics. You can greatly increase plant volume.

I've not used any of these products. My tap phosphates are 1ppm and before a water change the tank phosphates are 1ppm. Maybe adding a lot of plants, especially emergent plants and floaters would be a better way to control the phosphates. Plants with access to air (unlimmited CO2) grow faster and take more nutrients. The neons as well as the corys would appreciate more cover and dimmer light. There is no need for bright light in a low tech tank.

I just added two more pots worth of Moneywort as floaters. My Golden Pothos is supposed to arrive tomorrow.

Also I took the Renew out of the filter. As you can see I still have a bit of algae on the glass, but it's not covering the plants so I think they are starting to win the nutrient battle. I'm planning to do a small water change after cleaning the glass tomorrow before I add the Golden Pothos.

 

Why are you concerned with Phosphates? Are you having bad algae issues? Phosphates will come from the breakdown of organic matter (food, plants, dead anmimals etc.). You can feed less, and vac the substrate more to reduce organics. You can greatly increase plant volume.

I've not used any of these products. My tap phosphates are 1ppm and before a water change the tank phosphates are 1ppm. Maybe adding a lot of plants, especially emergent plants and floaters would be a better way to control the phosphates. Plants with access to air (unlimmited CO2) grow faster and take more nutrients. The neons as well as the corys would appreciate more cover and dimmer light. There is no need for bright light in a low tech tank.

Pothos have been added! I’ve definitely seen some plant growth too and the corydora seem happier with the extra cover above. Also the moneywort came with a sweet cardinal tetra sticker!

 

Cool. They look happy. The pothos will send roots all over the place and will even grow into the substrate. My fish like it. They swim around and hang out among the roots. In time they can be trimmed back as needed. I try not to trim them all at once in case it would shock the plant.

The pothos will grow and grow and grow. You either will have to trim it or train it. The new leaves will probably start growing bigger as well. At least that's what happens to mine.

 

This is before my weekly water change. There’s some algae on the sand and a few of the smaller plants but hardly any on the glass!