Alkalinity in ATO Reservoir

[boboze]

Alkalinity of my tank is plummeting rapidly. Can evaporation cause this? If so, should I increase the alkalinity in my ATO reservoir?

More information:

• Last week I used Red Sea KH Foundation to increase the dKH to 8.4. In 5 days it dropped to 5.3
• Calcium is stable
• Two days ago I added a C02 scrubber

 

[dwest]

No to evaporation. You might need to start dosing 2 part or other calcium and alkalinity replenishers.

 

[Randy Holmes-Farley Verified Community Expert]

Calcium always drops more slowly on a percentage basis, and two part additives account for that.

I’d look to rise about 1 dKH per day and see what happens. At 5 dKH, demand nearly stops.

 

[boboze]

No to evaporation. You might need to start dosing 2 part or other calcium and alkalinity replenishers.

Thanks for the quick answer! I should've added more info to my OP. I added two-part five days ago to raise dKH to 8.4 and since then it dropped to 5.3. Two days ago I added a C02 scrubber.

 

[dwest]

I would double check the alkalinity measurement. If true, you are going to need to increase your dosing. The scrubber should increase pH thus increasing alkalinity useage.