Just try the DIY yeast method to see if you like the results of CO2 injection. Be sure to wait 3-4 weeks to evaluate the results. In my tanks CO2 produces larger more robust growth, but my tanks without CO2 also grow plants and look nice. With CO2 I have to spend more time trimming the excess growth. Joe Hildreth 15 Cedar Street Potsdam,NY 13676 ------------------------------------------------------------------------- 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"!