. ..
Baking soda is sodium bicarbonate (NaHCO3).

When it is mixed with an acid liquid it releases the gas carbon dioxide

There are lots of ways to create CO2, but in terms of time, effort, or
cost, none are any better than a compressed tank of CO2. Yeast isn't
as stable, and takes time every week or two. Adding soda water works
for just an hour at a time, so you'd need to rig up a dosing system.
The electronic plate systems tend to be very pricey, and don't produce
enough CO2 for large tanks.

One create way to create LOTS of CO2 is to burn propane. Many
mosquito traps use a tank of propane, which is burned, and generates
LOTS of CO2. And the tank of propane used cost much less than you
would pay for compressed CO2. But, I don't think we will see propane
used anytime soon for aquatic plant growth.

Compressed CO2 systems are relatively cheap ($30-40 for a regulator,
$20 or so for a needle-valve, $50.00 for the CO2 tank) and once set
up, are practically maintenance free. I haven't messed with my CO2 in
about a year. I've got a 10lb cylinder, and the tank pressure is just
now dropping down into the "replace cylinder" range. In the past two
weeks, it's gone from 800psi to 600psi, but the bubble rate is still
steady, no signs of the "end of tank dump".



Chuck Gadd
http://www.csd.net/~cgadd/aqua

. ..
Baking soda is sodium bicarbonate (NaHCO3).

When it is mixed with an acid liquid it releases the gas carbon dioxide

There are lots of ways to create CO2, but in terms of time, effort, or
cost, none are any better than a compressed tank of CO2. Yeast isn't
as stable, and takes time every week or two. Adding soda water works
for just an hour at a time, so you'd need to rig up a dosing system.
The electronic plate systems tend to be very pricey, and don't produce
enough CO2 for large tanks.

One create way to create LOTS of CO2 is to burn propane. Many
mosquito traps use a tank of propane, which is burned, and generates
LOTS of CO2. And the tank of propane used cost much less than you
would pay for compressed CO2. But, I don't think we will see propane
used anytime soon for aquatic plant growth.

Compressed CO2 systems are relatively cheap ($30-40 for a regulator,
$20 or so for a needle-valve, $50.00 for the CO2 tank) and once set
up, are practically maintenance free. I haven't messed with my CO2 in
about a year. I've got a 10lb cylinder, and the tank pressure is just
now dropping down into the "replace cylinder" range. In the past two
weeks, it's gone from 800psi to 600psi, but the bubble rate is still
steady, no signs of the "end of tank dump".



Chuck Gadd
http://www.csd.net/~cgadd/aqua