White chalky stuff

[freddie40]

My sump is getting covered with a white chlaky residue. I am assuming it is the Baked Baking soda (16 oz of recipe 1 per day) that I am adding to my tank. Is this forming for any particular reason? How can I stop it from forming?

Thanks,

Dave

[bertoni]

The precipitate is likely calcium carbonate, as you suggest. The high pH and high alkalinity that results from dosing the recipe 1 into the sump might be an issue. You could add the supplement to the display or add it more slowly, to allow more mixing to occur. What are the calcium and alkalinity in the tank?

[freddie40]

Alk is usually about 8, calcium is about 450.

Dave

[Randy Holmes-Farley]

How high does the pH get when you add the solution?

Ever measure magnesium?