Two way Anova with replicates

In the following expt I am pretty sure that I have to use a 2 way ANOVA but nevertheless any advice is welcome.
I have exposed phytoplankton to three concentrations of carbon dioxide, conc 1, conc 2, conc 3 and measured their growth as Fluorescence for a time period of 2 to 16 hours every 2 hours. So i have 2 factors ie diff CO2 levels and Growth due with time.
In addition I have 2 bottles of phytoplankton each exposed to one conc of CO2, so 2 bottles of Conc 1, 2 bottles of Conc 2... These constitute my replicates. The question is am i correct to choose 2 way ANOVA and how do I treat the replicates.
My question is kind of like
but i dont seem to understand the response. Also i dont work with Mini tab but use an older version of Statistica (6) and SigmaPlot 12.o
Thanks a lot for any help!