It is definitely possible. A lot of us don't use added CO2 and some of us (@_Maq_ ) don't use a filter.making a planted aquarium, without co2, without a filter.
what? why ? is so bad?Oh no, not Walstad again...
Yes. Her book is bad. She's not a honest scientist and she's poor practitioner. She's definitely not the one to advise how to do our hobby.what? why ? is so bad?
I'm much <"keener on her"> than @_Maq_ is.what? why ? is so bad?