"If it were me with this dilemma, I might use it as an excuse to buy a bigger tank! [...] That should solve most of your problems." (Gnome et al 2004)gnome said:But I cannot get the darn CO2 level past like 3 ppm! I'm NOT going to get a pressurized system for a 4-gallon tank, though.
Gnome, Naomi et al. "Need a bit of help." Internet: Aquatic Plant Central, 2004. pp. 12802.