Hi all,
I have manager to set-up a planted aquarium, with no fish.
I pump CO2 by 3 DIY 2L bottle.
I week ago I introduce three black mollies, three are all fine.
Two days ago, I introduce 20 Neon Tetras, 10 Cardinal and 20 Rummy.
Disaster, yesterday four fish cardinal 1 Rummy died.
I my...