I know, sounds silly. But for some reason NO place around here sells it...no lie. Everyone sells Seachem Flourish, just no Excel. One store had some cheapo CO2, which might work, I don't know. I just want to get something reliable though. I want to try this out on my new planted tank and am looking to see if anyone has some extra that they possibly don't want or need. I would order online but the shipping is just as much as the bottle. Can anyone help a fellow aquarist out? If not, PM me with another alternative brand for liquid CO2.