I have been reporting over the years about how the hobby has been helping to shape the world of conservation and restoration. Last week I came across this article and I wanted to share it with you.

We have been using kalkwasser (calcium hydroxide) for decades because of the numerous benefits that it provides in our home aquariums and many people have, over the years, experienced a great amount of success putting calcium hydroxide into their application.

In simple words Kalkwasser:

  • maintains calcium, alkalinity
  • increases pH by removing both carbonic acid and CO2 from the water when producing carbonate and bicarbonate ions
  • binds to phosphates, lowering the level of the nutrient a bit
  • is extremely cost effective

Julian Sprung, who brought kalkwasser to the United States, explains kalkwasser.

Chris Meckley refines the method for commercial application and gets explosive coral growth.

Going back to the story, “ocean liming” is the technical term for using calcium hydroxide (kalkwasser for us) in the Apalachicola estuary of Florida’s panhandle area to restore the oyster population that’s been affected by ocean warming and the rising carbon dioxide levels which made the area’s water much more acidic (Lower pH equals bad. Sound familiar?).

Apalachicola Bay produces about 10 percent of U.S. oysters and the number of oysters from the region has been dwindling over the years, which prompted the government to step in and impose a ban on oyster harvesting for 5 years. You can imagine what kind of impact that it had on the market and the lives of the people around the region, but when that ban wasn’t producing the results that were needed, they realized that they had to take a different approach.

They chose an drastic approach to combat this. I say drastic because in my previous experience of working with the government, I learned first hand how careful they are in adding something to water to fix things. It’s extremely tedious work and you have to fight constant battles to get your point across, and even then it’s hard to get the results that you want, regardless of what the science is telling you. So for me to see that the government has decided to go ahead and utilize a large volume of calcium hydroxide to fix the imminent increase of CO2 levels was extremely surprising.

We have seen what happens when you overdose kalk in your system, right? While kalk has its benefits, when utilized inappropriately and carelessly, it can potentially nuke the ecosystem that it’s supposed to help. In reading the original article, it seems like they are aware of potential issues that this can create and they want to do this in the field but not at the expense of the animals. As a hobbyist, I would really love to see if they can reach out and tap into the knowledge of Dr. Craig Bingman or Julian Sprung, who have been championing this for decades and know all the ins and outs.


A nontoxic dye tracked a plume of lime that neutralized acidic waters in a Florida estuary.

Scientists recently had success in testing small patches of the estuary, injecting 2000 liters of calcium hydroxide into the water.

I will be keeping my eye on this project, observing the long term effects and how they will do this without negatively impacting the animals in the surrounding area with the immediate pH spikes, but I am also very happy to see that they are taking real steps and measures to fix the oceans. In this case, with a method that is so familiar to us.

If you want to read about the OAE or Ocean Alkalinity Enhancements, you can read it here.

Source for this article is found here.

Have a read. It’s really interesting!

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