most fish will be gasping for air at the surface. I found neons were affected and Rasbors showed no signs of too much CO2
Not necessarily true.if you use a drop checker it will not be accurate unless you use 4dkh
-- On the contrary, Hoppy. You have quite well clarified the options :icon_lol:.I also recall Tom Barr telling me that bigger fish are less (more?) susceptible to CO2. Unfortunately I don't recall whether it was less or more. (Big help, huh?)
http://www.plantedtank.net/forums/fish/53805-roseline-sharks-puntius-denisonii.htmlI have 9 in a 350 gallon.
Also, the larger the fish, the more suspeptible they are to low O2 and high CO2.
Not the other way around, ...