Cory Health Problem? Help!

[kickoutthejams]

I'm new to aquariums and am in the process of stocking my first tank. It's a 30 gal tropical aquarium. I followed all the guidelines carefully, gave the tank 2 weeks in operation before adding the first fish, have been monitoring PH (currently 7.4), ammonia etc carefully and have a mix of real and synthetic plants in the tank with a water temperature of 23c. I began with 4 peppered corydoras, and added 6 guppies two weeks later (4 female, 2 male).

One of my corys is acting strangely. He/she swims near the surface then shoots up, and gulps air from above the water. He will do this a few times, then swim back to the bottom of the tank and lie on the gravel for a wile before doing it again, sometimes spitting a bubble or two from his mouth whilst there.

I know Corys will get air from the surface if there is not enough oxygen in the tank, but I did a test and the oxygen levels are fine. None of the other corys are acting this way. I have a quarantine tank (4 gal) but it has only been running for about 4 days so I would prefer to avoid using it. I have added aquarium salt to the main tank as I believe this helps gill functions.

I've not had the fish long and it would be awful if one of them died. I would greatly appreciate any advice.

Thank you!

 

[catfishmike]

what do you mean by lay on the gravel?and when you say that the others arent acting this way?what are they doing then.everything seems fine from what you say as many corys can just be quirky but the part about laying on the gravel sounds bad.
try to elaborate more and write back

 

[kickoutthejams]

Having spent plenty of time last night watching the corys, he/she seems to be ok. When I mentioned laying on the gravel, the cory would just lie there and not move much at all after making his oxygen trips, whereas the otherfish would be swimming about searching for food.

I fed them when I got home yesterday and he seemed to be happily feeding and generally much more active so perhaps I was worrying about nothing!

Thanks for the reply.

 

[Scrumpy]

My peppered corys do exactly the same thing. They all have different characters...I've got playful corys, grumpy corys...the lot. Don't worry!
BTW...don't add too much salt. Corys don't like it much...they don't have scales quite like other fish and they and a few others aren't keen.

 

[kickoutthejams]

I added about half the suggested amount, as it seemed an awful lot to me. The more I watch that cory, the more it seems like he's actually playing with the guppies! He swims around with them almost as much as he does with the other three corys, and the males guppies in particular seem fascinated by him. It's almost as though he's showing off to them!