Fire in your grow room? Surely you jest, Holmes! No, Watson, ’tis true! And with good purpose! Hot air in this case is CO2.

There are a lot of CO2 generators on the market, varying by capacity. Connecting either a propane or natural gas line, a generator burns gas to produce CO2. When the burner is on, CO2 is generated. When it’s off, not.

Controlling this with an electronic CO2 controller will avoid wasting gas and create the exact environment of your choice.

Alternatives to using a gas-burning CO2 generator include the yeast/sugar soda bottle method (very imprecise) or a CO2 tank with a CO2 regulator.

Hydro Innovations’ MiniGEN is a compact CO2 generator and comes in at 6″x7″x10″. It’s small and adorable. Like Pikachu, small packages can generate powerful results.

Included accessories

– AC adapter
– 2 small screw hooks to screw into the top of the MiniGEN (for hanging)
– 2 worm-gear hose clamps for the water-cooling hose bibs
– 2 mounting screws for mounting the unit against a wall or wooden support
– 12-foot gas line with regulator for your propane tank

Setup & Installation

– Connect the included gas hose to the MiniGEN and a propane tank.

– Either hang the MiniGEN via its included screw hooks (good metal ones, too!) or flush-mount the unit against a wall. I opted to use ratcheting rope hooks with the screw hooks, but standard light chains would be fine.

– Plug the AC adapter into the MiniGEN and then into your CO2 controller.

– Slide the water hoses onto the hose bibs. The water hoses slide easily onto the front hose bibs for the MiniGEN. Cinch down the connections with the included worm-gear clamps and you’re good to go. I only wish that all of Hydro Innovations’ gear used these hose bibs. Easy on and easy off.

– For added measure and because I am paranoid, I teflon-taped the MiniGEN water hose bibs. As a former Boy Scout, I believe that added safety breeds security. No exception here—albeit the directions specifically state that these measures are not required.

Operation

Once everything is connected, your CO2 controller takes care of the MiniGEN.

The MiniGEN does have an on/off switch. Prior to walking away from your installation, ensure that you turn this on. The switch proves very handy when working around in your grow room. No need to waste CO2 with your grow chamber open—flip the switch to ‘Off.’

One exception to using a CO2 controller. If you are using CO2 as a natural pest-killer (around 10,000 PPM), you won’t use a CO2 controller. OR, you’ll use one that allows you to specify 10,000 PPM as an acceptable level.

Not only will this eradicate all pests in your grow room, you may eradicate yourself if not careful. Show extreme prudence if you attempt this sort of CO2 application.

Performance

Once connected, the MiniGEN takes a few clicks (of the electronic ignitor) to light the propane. I watched the CO2 controller. Two minutes later, the indicator crept from 500 PPM to 1500 PPM CO2 and turned off the burner. The MiniGEN’s burner generates 1.5 cubic feet/hr of CO2.

My grow chamber is 4′ wide, 3′ deep, 7′ tall. I hung the MiniGEN slightly above my light reflector and laid the CO2 controller slightly beneath the plant bases—approximately 3 feet between the two. This way, I ensured that at least 1500 PPM CO2 flowed across all levels of the plant tops.

Heat

A common issue with CO2 generators is heat. Pure and simple, fire is burning the propane to generate your CO2. Fire = heat. What to do with it?

The good folks over at Hydro Innovations solve that problem with all of their CO2 generators by water-cooling the units. Using a water chiller and pump with the MiniGEN, my grow room sees no added heat—at all.

If you’re running the MiniGEN without the water cooling (which you can do), you will need to add some sort of environmental cooling (ala conventional air conditioning or via a Hydro Innovations IceBox setup).

Safety

For being such a small unit, the MiniGEN incorporates two cool safety features:

– The electronic ignitor turns on only when CO2 is to be generated. No pilot light. Not only does this eliminate an unnecessary active fire in your grow chamber, but it conserves gas.

– An anti-tip sensor will not allow the ignitor to trigger if the unit is not level. If the unforeseen happens and the MiniGEN falls down or tilts, the unit will not fire.

How to make it better?

For once, I’m stumped.

The only suggestion that I can offer is a visual indicator of propane flow. I have not run out of propane yet. When I do, the only indicator will be the constant clicking of the MiniGEN’s ignitor. If I’m on an extended trip, this might last several days.

A visual indicator of either the flame or the gas (flowing/not flowing) might work well. However, on the MiniGEN itself, this would be less than ideal because you would need to open your grow room to see the indicator. Instead, the included 12′ propane hose should be substituted for one with a flow indicator on the tank side.

Other than that, this is a simple, perfect little beast.

Conclusion

If you have a grow room on the medium to small size (10′ x 10′ x 10′ or smaller) or otherwise don’t need super-fast CO2 flow, the MiniGEN is YOUR CO2 generator.

Simple. Cool. Efficient. Safe. Enough said.

Happy Gardening,

Curtis