I have one of these on my planted aquarium. The regulator has a solenoid connected to a pH probe in the tank's water. As CO2 is injected, to fertilize the plants and enhance their growth, the pH of the water drops. This increases the acidity of the water. No big deal for the plants, but the fish may be affected by the drop in pH. The solenoid allows for CO2 injection as the pH rises above a predetermined level. You should be able to just remove it and it will work fine for you. As for the tank, it's the same as the ones we use for our brew. In fact, there has been more than one Sunday I was glad planted tanks was another hobby of mine because that tank in my keg fridge crapped out and I was able to pirate the tank from my aquarium to push beer. Drinking beer trumps photosynthesis just like rock beats scissors!