Bronze corydoras

[mbsqw1d]

If you are following the dose as per the instructions on bottle for the ferts, given the amount of plants you have, I would probably dose at half the rate at the most. The tank in my signature I dose TNC ferts at half the recommended dose and have no issue.
If you are dosing an amount too high for the amount of plants (and the type, ie anubias is slow growing), if the plants arent using the nutrients you provide, then that can build up. If the ferts contain calcium and magnesium then you'd be rasing the GH which could adversely affect the fish.
I'm not saying this is why the cory has been flashing, I'd agree with NCaquatics' point about the fish adapting to your tank's water (the LFS probably doesn't dose ferts etc).

The cory's belly did look a little bit sunken to me, but again, as its new it just needs a good feed after being at the LFS which I'm sure you'll sort out no problem

Edit: also I agree with essjay, I wouldn't use the liquid carbon given it's ingredients (unless it was a plant only setup). Its best to look at providing extras for plants after you notice plants showing some deficiencies. Most plants do ok with fish waste (nitrogen and co2) and food waste (phosphate) alone. The micronutrients (zinc, iron, manganese, boron...) you are supplying with a small amount of liquid ferts.

 

[Anthony1976]

Hello,
I have bought, only yesterday, 3 more bronze corydoras in the pet store to add to my 64L tropical tank and I have noticed one of them scratching on the sand. Is it something I should worry about? My water was tested yesterday and all the parameters were good. The tank is currently heated at 25 degrees Celsius. I would really appreciate your advice. Thank you!
Céline

i know with my bronze Cory’s they flick the gravel when they are trying to disturb the substrate to kick food up which is a totally normal behaviour for them. Could yours be doing this ? As they do look quite healthy .

 

[Celine]

Thank you for all the advice. I will definitely reduce the dose of fertilizer in my aquarium and leave the CO2 out.
I am due a water change today so hopefully this will help the fish too.
Regarding feeding, I usually feed my fish once in the morning. Do you reckon this is enough? Or should I feed them more often?
Thank you!

 

[mbsqw1d]

I feed mine a couple of times a day. As catfish are very active at night I tend to throw some pellets in before I go to bed, and then give them a little food during the day. I think if you can feed smaller amounts a couple of times a day that is better suited to their natural scavenging behaviour where theyre effectively constantly eating tiny infusoria.
Someone on here said that the amount of food should be the size of the fish's eye. For me that equates to approx one pellet per three corydoras. If they have finished what you have put in before 1 minute then it might not be enough.

 

[Celine]

Thank you for your message. This is very useful information for me