Do you have any pH buffers (phosphate) in your tank? They will through off your CO2 calculations. With a bubble counter, I find that I can see changes in CO2 concentration within an hour (especailly after a water change where CO2 goes from 3ppm back up to 20+ ppm.) As a reference, my 20g runs at around 2 bpm and my 45 gal at around 3-4 bpm both targeting around 25ppm using bubble counters (but it is darn tough to read the color accurately and the valvles need adjusting every coupled of days.) -john On Fri, Jan 8, 2010 at 12:37 AM, Matt Staroscik <matt@wrongcrowd.com> wrote: > I set up my CO2 system to deliver 1 bubble per second at 9 PM. Not having a > reactor yet, I fed the output into my Fluval canister filter. There was a > small burp every 30 minutes but the filter didn't seem troubled. I am sure > I > am not getting the best efficiency but next week I will have a better > diffuser and a drop checker. > > I use RO/DI water for the tank and keep cuttlebone in the filter. (I know I > don't really need RO/DI water but it's awfully convenient the way I have it > set up. Using tap water would be more work.) Before CO2 injection started, > at 9 PM the tank was pH 6.8 and 3 dKH. > > At midnight lights-off, the pH reading was still 6.8, maybe a tiny bit > less. > This corresponds to 14 ppm CO2, assuming that any CO2 dissolved at all and > I > am not seeing some other buffering screw up the relationship. I have a lot > of wood in the tank and have heard that tannins screw things up. > > Is 3 hours enough time to bring the tank to a new steady state? It seems > strange that pH didn't change, but my test kit only runs in 0.2 pH unit > divisions so I could have dropped a full tenth and not known it. > > I guess I was expecting to see SOMETHING change. Time to get out the pH > meter from the old reef equipment box, I guess! Perhaps 1 bubble per sec > just isn't enough gas for my setup's efficiency. > > MS > _______________________________________________ > GSAS-Member mailing list > GSAS-Member@thekrib.com > http://lists.thekrib.com/mailman/listinfo/gsas-member > _______________________________________________ GSAS-Member mailing list GSAS-Member@thekrib.com http://lists.thekrib.com/mailman/listinfo/gsas-member