I am starting up a 55G planted tank. Want to fill it with angels and neons. Purchased 8 neons the other day. Split them between 2 quarantine tanks. 5 died overnight. Heard they are tough to keep/get started. Does this happen quite often with neons, high mortality rate? What are recommendations for tank parameters in keeping them and getting them accustomed to new tank? I typically have higher ph around 7.8 in most tanks. Planted tank, with CO2 has been around 6.8. The planted tank has no fish yet. Thanks for any ideas.