I have just started with plants, and I went with the Aquatek Deluxe system. However, I didn't realize that I would need a bubble counter anyway because even at 1 scfh (measuring units for the meter) the valve and flow rate monitor lets out too much CO2 for an aquarium. The deluxe model seems to be more for green houses or aquaponic systems. I barely crack the metering valve for the flow rate that I need, which leaves the meter virtually useless. It seems to keep a fairly accurate rate so far, but I've only been using it for a few weeks so maybe someone who has been using it for a while will chime in.