@ncguppy: did you see his water'quality??? the tank is so dirty, and pump still keep his fish in that tank...as i can see, he still don't change his water...
So far no more dead fish in the tank but now I'm wondering if after I get my Anti-protozoan flakes I should go ahead and treat the survivors for parasites.
How old are the guppies? They may have just reached their time. I've recently just had all of my female guppies that I've had for about a year or so have died off but the newer generations are doing fine. That might be it.
Oh god, it's sad to say the same thing happened to mine even the younger ones - I cleaned the tank completely and now everything's fine and has been for a few weeks.