fish dieing suddenly, no symptoms

[mumrah]

recently i added a pair of guppies to my 10g community tank. the next day, the female died. the next day i added another female, the following day she and one of my 6 neons are dead.

Please help before my whole stock is kaput.

-David

[Blackpearl]

what are your water params? did you quarantine the fish before adding to the tank?
are all your fish seem fine and swimming as usual? notice any different behavior?

[mumrah]

parameters are normal

nitrate 10
nitrite 0
ph 7.8

i dont have means to test ammonia, but i suspect it's ok since the nitrates are fine. I'm taking my water in to get tested today.

the 5 other tetras, male guppy, and pleco are all happy and behaving normally.

i did quarantine the female guppy before adding her, but only for 4 hours or so.