I moved my angel to her new home, left her for a week then added new tanks mates, all of whom look great, water's great (so far) etc. But I'm still having problems w/ the original 10 g that she was in.
I had a F guppy and a tetra in the tank who were doing great for a couple of weeks after we lost a few others due to lousy water. So I added a pair of guppies another tetra and a Pleico. The two guppies dropped dead in two days. Then my old tetra died. I think I'm having a heater problem because the tank was at 81 (I usually keep it about 76-78) and I could not get it to turn off. But I also had left the light on during the day (which I had not done previously) because I was told that they should have eight hours of light a day, so that may have also contributed to heating the tank? I'm going out to get a new heater now, since it looks like the thermostat is shot. Could that be causing all the probs? Or could the guppies have brought something into the tank? The guy said they'd only been at the store for three days, and there was a dead one in the tank- he said it was probably just the stress of transfer. They looked very healthy at the time. Now my original guppy is looking off, her fins are a little folded, and she's usually very perky. The water is testing perfectly in all areas, same as 55g. What am I doing wrong?
Thanks for your help!

personally if i wasn't absolutely sure of the source of the fish(i.e. supplier and lfs) i would quarantine any new fish for a couple weeks. i think that may have been your problem.

Thanks-
I did go in and read up on one of this sites links and it said the same. Nest time I'll know. Remaining three fish seem fine. I'll wait a month then try again.