How to Raise pH in a Reef Tank?

Most reef tank owners know that a steady pH is essential. Generally, you want it to be 8.3 or as close as it can. This number represents the right metabolic processes, health, and coral growth.

You may find that a slightly lower or higher pH works best for your ecological system. Still, you want to make sure that the numbers are steady. If you find that your tank’s pH is too low, there could be various reasons.

Many times, low pH problems are caused by too much carbon dioxide or low alkalinity. The pH number is actually a scale of acidity ranging from zero to 14. Alkalinity is what allows the water to neutralize the acid and carbon dioxide levels.

This is directly related to how much carbonic acid is in your tank. Therefore, you can achieve a higher pH level by lowering carbonic acid amounts and neutralize more acid. Here are the ways to do that:

Expert Tips For Raise pH in a Reef Tank

Maintain the Right Alkalinity

Alkalinity is always the first thing you should check when maintaining and monitoring the reef tank. It is more important that pH, magnesium, and calcium. In certain situations, it could even be more essential than salinity.

Most experts recommend that you try to get to 8.5 dKH. This safe range allows you to test and dose for mistakes without running into too many issues. If the alkalinity goes slightly up or down from there, it’s not going to hurt the ecological system very much.

You can use a water and sodium bicarbonate solution to raise the alkalinity. Consider using a reef calculator, too, to find the right dosage for the tank. Don’t use any product labeled as a pH Buffer, as those products could contain other ingredients you don’t want.

Often, these products just have sodium bicarbonate, though. You’re paying more for the packaging. Though you don’t have to figure out the dose yourself, it’s usually safer and less expensive to DIY.

Don’t forget to think about calcium. Both alkalinity and calcium are consumed at the same rates. Therefore, you should maintain each regularly after you have reached the target levels.

For most reef tanks, this is achieved with a two-part solution. However, you can use a single additive. Just make sure that it has calcium and alkalinity in it.

Typically, a kalkwasser (calcium hydroxide) and calcium reactor are used. However, it works best when you’ve got some experience and know what you’re doing.

Alkalinity and Calcium Supplements

If you choose to use a two-part solution, consider those made of kalkwasser and soda ash (sodium bicarbonate). Both of these products can reduce the carbonic acid in the water and raise pH levels. When you need a supplement to help maintain alkalinity, you can choose either of them or both.

Reduce Carbon Dioxide

Sometimes, the area around the tank (outside) has high carbon dioxide levels and lowers the pH. Most rooms and homes are tightly sealed for energy efficiency. However, this also means that more people and pets are breathing out carbon dioxide throughout the day.

These elevated CO2 levels can increase the pH level of your reef tank because more natural gas exchange happens. The easiest fix for this is to open a window in the home to let in some fresh air. Consider doing this a few hours a day and monitor pH levels to see if that helps.

If opening a window does raise the tank’s pH level, continue to do this when you can. However, it’s not feasible to keep windows open in the summer or winter. It’s possible to purchase and use specialized equipment, such as an air exchanger, for year-round help.

Get Fresh Air from Outside or Scrub the Air for the Skimmer

The protein skimmer in your tank is essential and helps create the gas exchange. In fact, it does more than the water at the surface, interacting with the ambient air. Therefore, if you’ve got issues with CO2 levels, pull fresh air from outside.

This might require you to run a tube through your wall. That way, the air outside gets directly into the protein skimmer. Usually, this boosts the pH levels in the reef tank.

When doing this, make sure that pesticides and fertilizers don’t contaminate the air. Though they go on the ground, they can still be present in the air. This could add chemicals to the reef tank that damage the ecological system.

To offset that, consider adding carbon to the intake side. This is a great safety precaution and can remove any contaminants and pollutants before they get into the water.

Alternatively, you can use a scrubber to remove the carbon dioxide. You get a sealed canister like a BRS reactor that has CO2-absorbing media in it. This gets attached to the air intake tube, removing CO2 before it gets to the skimmer.

Of course, this method is highly effective in elevating pH, but it can work too well. Be careful if you run a strong skimmer that has significant flow-through rates. You may need to use a WYE fitting to throttle it back, or the pH goes too high.

There is a way to automate the process with an electric solenoid. Attach that to the CO2 scrubber’s WYE fitting. Determine the best pH level from the controller and let it open/close the value as needed.

This maintains the right 8.3 pH number. As the pH dips, the valve closes to force air through the scrubber. When pH levels get too high, the valve opens to pull in ambient air.

Use Macroalgae

If you use refugium-growing macroalgae, it eats the extra carbon dioxide in the water. Chaetomorpha is great at reducing the carbonic acid to raise pH levels.

Sometimes, this is the best method. It’s natural, so you don’t have to buy anything else regularly. It is also well-suited for those who want to put in that effort and tune growth rates by adjusting photoperiod and light intensity.

Conclusion

There are countless ways to raise pH in a reef tank. You may need to test out a few options before finding one that suits your lifestyle and needs. However, don’t neglect pH levels because this could do significant damage to the ecological system.