Okay so this afternoon I got 11 cardinal tetras. Drip acclimated them for 2hrs and proceeded to but them into the tank with lights off. Left and went fishing for awhile got home around 10pm and I went and turned my moonlight on. Then I ate dinner and went to go watch my new fish. I started to count them and I only got 9. Two were missing so I start looking around and one is floating ontop dead while the other is dead under my wisteria. So trying to figure this out I tested my water and my results were: 0 ammonia 0 nitrite 10 nitrAtes 7.6 Ph Should I just chalk this out to them being new and weak? Or is something wrong? All the other tetras are zipping around the tank and some are playing in the filter outtake swimming up and down.