How To Raise pH Using A Co2 Scrubber?
If you’ve been in the aquarium hobby for some time, or even if you are a newbie reef enthusiast, you may have encountered issues with controlling the pH inside your reef aquarium. For example, you may have taken the pH reading one day and it is perfectly sitting within the desired range, and then next, you are scratching your head wondering why it has dipped down the pH scale. Sounds familiar? Well, do not worry, we’ve all been there, and with our team’s knowledge, we are here to give you a nifty solution that will help - a CO2 scrubber!
Why Does pH Drop In Aquariums?
Before we dive right in, it is important to understand why pH drops in the first place. The most common case is too much carbon dioxide (CO2) in the aquarium water. Now, you may be thinking “Where does it come from as I’m not injecting it into my tank”.
In reef aquariums, CO2 naturally builds up from the following:
- Corals and other marine invertebrates that release CO2 during the night
- Bacterial processes such as breaking down waste
- Fish and other aquarium critters during respiration
All of this combined CO2 dissolves into the aquarium water, forming carbonic acid (H2CO3), which lowers the pH inside your aquarium. In nature, the ocean can easily dilute this CO2, but in our closed aquarium systems, not so much.
What Is A CO2 Scrubber?
But as we said earlier, do not worry as this is where our hero of the day enters - the CO2 scrubber! A CO2 scrubber is essentially a filter for your tank’s air, not the water. Its job is simple. It removes the excess CO2 from the air before it dissolves into the aquarium water. And the result - a more stable, higher pH level that will keep your corals and other aquarium friends happy and healthy.
How Does A CO2 Scrubber Work?
The magic behind a CO2 scrubber is a chemical reaction which uses a substance called soda lime (CaHNaO2) - a mixture of sodium hydroxide (NaOH) and calcium hydroxide (Ca(OH)2). When the air containing CO2 passes through the soda lime, the CO2 is ‘scrubbed’ out via a chemical reaction.
To break that down, here are some simple steps of what happens:
- Firstly, the air from your aquarium tank’s airspace is pumped through the CO2 scrubber.
- Next, the air comes into contact with the lime soda inside the scrubber.
- The CO2 in the air then reacts with the soda lime, forming calcium carbonate (CaCO3) and water (H2O).
- Finally, the cleaned air containing less CO2 is returned to the aquarium tank.
The process is quite literally giving your tank a breath of fresh air!
How To Set Up A CO2 Scrubber?
Now we have covered the basic workings of a CO2 scrubber, let’s discuss how to set one up. If you are a new aquarium hobbyist, do not worry as it’s not as complicated as it may sound.
First, select your CO2 scrubber. There are many commercial options available, but for those DIY enthusiasts, you can build your own - which we will go over a bit later on. However, whichever route you decide to go down, here are the basic components that you will need:
- An air pump
- Soda lime
- A container to hold the soda lime
- Air-tight tubing to connect everything
Setting it up:
- First, fill your CO2 scrubber container with sodium lime. You will want to leave some space at the top to allow airflow.
- Secondly, connect one end of the tubing to the air pump and the other end to the input of the CO2 scrubber.
- Next, run another piece of tubing from the output of the CO2 scrubber back to your tank or sump system.
- Finally, turn on the pump and let the CO2 scrubbing start!
Top Tip: We recommend placing your CO2 scrubber’s output near your skimmer or another area of high surface agitation - this helps the clean air mix better with your tank water.
How To Make A DIY CO2 Scrubber?
For those who love diving into a DIY project (let’s face it, what reef hobbyist doesn’t?), building your own CO2 scrubber can be an enjoyable and rewarding process.
Materials:
- Soda lime
- Air pump
- A large plastic bottle - make sure that it is clear
- Airline tubing
- A drill or something to make holes safely in the bottle cap
A step-by-step guide:
- First, you will want to clean your bottle thoroughly and let it air dry.
- Using your preferred tool, drill 2 holes in the bottle cap which are large enough for you to fit the airline tubing snugly.
- Next, cut a piece of the tubing, ensuring that it reaches from the bottle cap to near the bottom of the plastic bottle when it is in an upright position.
- Thread the longer tubing piece through one of the holes in the bottle cap, leaving the long tubing on the outside - this will be your input tube.
- Thread a shorter piece of tubing through the other hole you made in the bottle cap - this will be your output.
- Next, fill the bottle approximately ⅔ full with the soda lime and screw the bottle cap on tightly.
- Finally, connect the input tube to the air pump and the outer tube back to your tank or aquarium sump.
And voila, you would have built your own CO2 scrubber!
Top Tip: Remember to replace the soda lime when the color starts to turn purple or brown.
Monitoring pH
Once your CO2 scrubber is up and running, you can’t neglect your rank. You need to keep an eye on your tank’s pH and see how things are improving.
- Remain consistent - test your pH with a pH probe at the same time each day
- Track your process - remember to keep a log of the pH readings
- Be patient - results may not happen overnight, so give it a few days to see any significant changes
- Try not to panic over small changes - remember that in the day, pH naturally fluctuates
Additional Tips For Stabilizing pH
While a CO2 scrubber works wonders in raising the pH inside reef aquariums, it is important to note that it is only a small part of maintaining a healthy reef tank. There are many other factors, such as:
- Performing regular water changes to replenish buffers and remove excess nutrient
- Feeding your livestock correctly to reduce waste and CO2 production
- Ensure your aquarium has a good water flow system and surface agitation to boost oxygen exchange and CO2 off-gassing
- Use a high-quality salt mix
- Maintain proper alkalinity levels
Summary
And there you have it - your guide to raising the pH inside your aquarium with a CO2 scrubber. Remember, whether you choose to buy a CO2 scrubber or be adventurous and create your own DIY scrubber, they are valuable aquarium equipment that will effectively solve those pesky pH drops.
At Reefco Aquariums we understand that every reef tank is unique, and what works for one person may not necessarily work for someone else.
Don’t be afraid to experiment and see what works for your aquarium setup. However, if you have any questions about CO2 scrubbers or need help setting one up, do not hesitate to contact our experienced team here at Reefco Aquariums today. Happy reefing!
Featured image by Marcelo Kato from Pixabay
<a href="https://pixabay.com/users/marcelokato-4416261/?utm_source=link-attribution&utm_medium=referral&utm_campaign=image&utm_content=2580208">Marcelo Kato</a> from <a href="https://pixabay.com//?utm_source=link-attribution&utm_medium=referral&utm_campaign=image&utm_content=2580208">Pixabay</a>
