Dead cory habrosus -your diagnosis?

[memehuffer]

Hi all,

One of my wee cory habrosus was found dead yesterday... and after 2 or 3 inexplicable guppy deaths in the past 2 weeks. However, unlike the guppies, this one actually is exhibiting symptoms (although they must have happened quickly, as he looked perfect not 10 hours before he passed).

2 photos here:
http://s1301.photobucket.com/user/memeh ... 0.jpg.html
http://s1301.photobucket.com/user/memeh ... d.jpg.html

Some sort of internal infection/bleeding... no idea what though!

Tank (10G, planted) is cycled and totally stable (ammonia 0, nitrite 0, nitrate 10, ph 7.7... sorry, don't have hardness measures, but have been assured by my very local fish shop that our local tap is fine in that regards)... I did have a hidden guppy corpse a couple weeks ago, but that's out... since the deaths have started, I've been super vigilant with PWCs (25% twice a week) and gravel vacs, and did a 50% change after removing the dead cory.

My main concern is the other 3 corys, a dwarf gourami and 3 juvenile guppy in the tank... they all seem fine, but so did the guppies and the cories and then they were dead the next morning

I've went to LFS today, and was sold new spectrum Thera+ (for the garlic and vitamins)... asked the guy about whether I should dose the tank with broad spectrum antibiotics, but he advised against... he did recommend turning up the temperature from 77 to 80, though, which I've done.

So, anyone know what the little cory dies of?
And is there anything to do besides daily 25% water changes and gravel cleanliness?

[memehuffer]

Sorry, just read posting guidelines, and wanted to add some detail:

1" Gravel substrate (2-3mm, smooth)
Filtration: a top-mounted trickle kinda thing (its an AquaOne EcoStyle, so filter is part of tank... I've added some ceramic bio-media into filter box)
An airstone
plants and decos: driftwood, anubias, dwarf rush, riccia, red sword

[jodilynn]

I had bought Guppies at Petsmart and I would say 12 of them died in 3 weeks time, I buy three they'd die go back get three more they'd die...

Were the guppies new inhabitants? My guppies died of similar causes, sometimes they'd develop white patches and then bloody lesions, others would just die. If they were just introduced into your tank they could have infected the other fish.

I'm waiting to get a chance to call the manager of Petsmart back. I filed a complaint. Ridiculous! They were thankfully the only inhabitants of that tank so nothing else got killed off. I have one, yes ONE left!