I currently have
2 black neons tetras left out of 12 purchased and then later bought 8 more in 4 years.
they're in a 38 gallon and do fine. I count them everyday, lol
my last
neon tetra died a few months back, same issue. I had 12 originally, and then due to die offs my # fell, bought more. but they're so over breed &
diseases like 'neon tetra disease'- I'm letting them die off.
I'm tired of trying to sustain a school. I think you need 1 species only tank to make that successful really.
my 38 gallon has
cory cats, 2
mollies ( the 4 other mollies I purchased all died off, 3 in less than a month) and many, many male
guppies.
Moving any older fish just shortens their life imo
smallest skirt school I had was 3 or 4, they are super skittish. I'm of the opinion that
skirt tetras need at least 4 -6 to be happy and not super stressed.
I currently have 8 now and they do really well in my 20 tall tank.