Sick Emerald Cory Catfish, Not sure what is wrong

[goldfish1212]

the sick fish is an Emerald cory cat a little less than 1 inch

it has 2 white/clear blister like bubbles in the center of fore head about the size of a pin head, torn fin on top,and breathes much faster than the other fish

before I changed the water the tank tested nitrates=20ppm, nitrites=0ppm, ph=7.5,kh=180ppm,gh=30ppm, ammonia=0.20ppm
I use the API liquid ammonia test and the API test strips for everything else

my tank is a 20 gal, I think 20gal high but I 'm not sure, which has been cycled 1 month now(set up tank 2 months ago and levels good 1 month ago)

my filter is an 50 gal Aqua clear and I also have an airstone

the tank has 4 emerald cory cats, 4 albino cory cats all 3/4 to 1 inch long

I make a 25% water change and vaccum gravel every saturday (today is saturday). I put in a powder that is supposed to bring the ph to 7 to the new water before I pour it in the tank

I got the sick emerald cory cat along with 2 albinos corys and the 3 other emeralds corys 4 days ago from petsmart. I floated the bag in the tank for an hour, then added half as much water that was in the bag from the tank and floated them for an hour, then i poured them into the tank. When I got them they all appeared fine except for the one that is currently sick which had a small tear on the fin on its back.

I have not added any new rocks or decorations to my tank

I feed them spirulina tablets and goldfish pebbles, I give them a pinch of the the pebbles in the morning and then give them a broken up spirulina tablet in the afternoon. they also eat the green hair like algae that grows on the drift wood

WILL THIS SPREAD TO MY OTHER FISH???

 

[WhiteDevil]

Well pouring the bag of water in the tank was the 3rd mistake. Floating it for an hour was the first, then adding that much "new" water to the bag and floating it for an hour was the second one. When a bag sits in the water the O2 is depleted fast, and your readings are not ideal yet for them.

You can take that single fish back to petsmart as well.

Goldfish food is not suitable for corydoras. Give them a few spirulina tablets especially the younger corydoras as they are still growing and usually eat a minimum of 6 times a day on their own natural clock.

What size is the tank, what size heater and filter are you using? what is the temp of the tank? what is this powder?
I had a corydora for over a year with a missing membrane over her ear canal and nothing ever came of it but I havnt lost a corydora to anything in over 4 years now. You are better feeding the corydoras shrimp pellets then goldfish ones. Corydoras are 100% different needs wise then a goldie is.
Heck even the goldies I got that I dont want eat cichlid pellets. They wont touch their goldfish food.

 

[goldfish1212]

It is a 20gal tank with a 50gal aqua clear filter and a marineland stealh heater and I use sachem neutral regulator to adjust the water. The tank is 76 degrees farenheit.

I realize now that I acclimated them wrong, but I don't think that caused my fish to get sick. I'm pretty sure the fish was sick when I got it 4days ago.

Even if I do take the sick fish back I'm kind of worried that my other fish will get sick from being in the same tank as it. Do you know what causes small clear/ white blisters on a fish's face? I would like to know how to or if I should try to treat it.
I'll try to get better food pellets.

 

[shadyfish]

Just take it back to petsmart they have a 14 day return policy

 

[shadyfish]

And just so u know you should really try to stay away from petsmarts fish

 

[goldfish1212]

Thanks.I took the fish back and got the shrimp pellets.

 

[ejaramillo01]

Also i don't understand why you measure some levels with strips and the ammonia with a liquid test.

Strips are not accurate, be sure to buy a Master kit from API which will give you liquid test for ammonia, nitrite, nitrate, ph (high and normal). You need to be sure that your levels of nitrite are accurate.

 

[goldfish1212]

Ok. Thanks, my test strips are about to run out any way, so when they do I'll see about getting the liquid test.