I read a bunch of stuff online about CO2 in aquariums, and I think I am even more confused now! Some places say that the typical aquarium has a CO2 of about 2-5 ppm. But when I look at charts that correlate KH and pH (I have a KH of 3 and pH of about 6.8) it says that I have a CO2 concentration of about 15 ppm (which is good for most plant, right?). so which is correct? Do I need CO2 injection? Thanks!!! Eric ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Eric Martina University of Illinois Electrical Engineering ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!