Dying Lemon Tetras

[n3ont3tra]

Tank size: 29 gallons
pH: 6.83
ammonia: 0
nitrite: Unknown
nitrate: Unknown
kH: what's this?
gH: what's this?
tank temp: 74 degrees F

Fish Symptoms (include full description including lesion, color, location, fish behavior):
No color changes at all, no obvious wounds that I could see. The fish just sinks to the bottom, upside down, and dies. It wiggles and squirms, and tries to flip itself back over, but it just floats back around, belly up, at the bottom of the tank. It's very sudden, once I notice, it's dead in an hour. No behavior changes or anything.
Volume and Frequency of water changes:
about 15 percent every week
Chemical Additives or Media in your tank:
PH 7
Tank inhabitants:
5 Phantom Tetras, 6 Silver Tip Tetras, 4 Platies, 7 Neon Tetras, 1 3 inch Plec, 3 Panda Corydoras
Recent additions to your tank (living or decoration):
2 more lemon tetras to replace the dead ones. So far, 3 have died this way, maybe 4 (the fist one that died was killed the night we bought it, the second one the day after, and it had a little split in the fin, but it was so small I don't this it had anything to do with it.
Exposure to chemicals:
PH 7
Digital photo (include if possible):

I've had the fish for about 2 weeks in total, one just died about 20 minutes ago, and the last time one died was Friday.

 

[WILDER]

Take a sample of your water to the lfs need to know your water stats, tell them to write the readings down for you.
What do you feed the fish?.
Swim bladder and once it has progressed hard to cure.
For the rest of the fish cook some frozen peas for a few minutes, let cool down, pop out of shell, mush between fingers and add to the tank.

 

[n3ont3tra]

I feed them TetraMin tropical flakes, and I won't be able to get to a pet store until Saturday. Also, why is it only the lemon tetras? They were added at the same time as the platies, cories, and pleco, but they're the only fish to have died.

 

[WILDER]

Need to improve there diet with frozen foods and veg.
Sorry thought you had them longer, if there dying soon after you added them to the tank sounds like ph shock.
What is the ph of the lfs to your tank, and how long are you climatising them for.

 

[n3ont3tra]

I climatize them for half an hour in their bags, but the problem is, I ordered 5 online at aquariumfish.net, and after the first two died, we bought 2 more at the local fish store. Then 2 more died, and I have absolutely no idea whether it was the new ones or not.
What kinds of frozen foods and vegetables?

It's been a week since we got the new two, and 2 weeks since the others.

 

[WILDER]

When you get home with the new fish always test ph from the fish bag and temp.
This way you know how long to climatise them for.

Frozen foods can buy them in a pack of five different variety of frozen foods.
Veg anything green really.

Click on feeding.
http/www.skepticalaquarist.com/docs/health/viruses.shtml

 

[n3ont3tra]

ANOTHER ONE'S DYING -- RIGHT NOW!!! 8:45pm
Plese help, what do I do???!!!!



EDIT:: Why did these post combine?


It died.
That's how fast it happens. By the time I notice, it's too late.

Why's it only the Lemons? I've had the neons, phantoms, and silver tips in a completely uncycled tank, and they're all still alive...

 

[WILDER]

Bad batch, some fish are very sensitive, i would find another store if you want to carry on keeping them.
R.I.P.
Ph shock can take over a week to finish a fish off.

 

[n3ont3tra]

I got 5 from awuariumfish.net and 2 from my lfs though. There's only one left. I think it was one of the ones from teh lfs, and the one that just died was from aquariumfish.net cause of the size difference.

 

[WILDER]

Ok, i'm afraid it happens sometimes, I had a shoal of harlequins that died and did everything right.
Fish do have to go through alot of stress from tank to tank, even imported from the wild you can understand why so many of them don't make it.
I would just put in down to a bad experience and move on, and maybe try another lfs.