Alk increased over +2 with no changes in dosing

[doesitwork]

Have a large 8ft tank roughly 600G system. I've been battling managing my ALK for the last several months. I use a Neptune Trident to dose 32ML ALK / 20 ML Calc each day. Goal of keeping my alk at 8.15 +/- 10

ALK is 79 doses every 18 mins rotating .4 mL to .8 mL each time.
Calc is dosing 100 times .2 ML every 14 mins.

For the last 3 weeks it's been consistent 8.1-8.25 which was perfect. This past week I had a huge spike to 10.56 without making any changes to the dosing. Do you think the Neptune pumped to much in or could there be other factors that affect alk?

Coral: I have around 50 torch heads, and maybe 12 of them have bailed out among losing several SPS.
latest ICP test (within last 2 weeks): https://www.triton-lab.de/en/showroom/icp-oes/235442

 

[Randy Holmes-Farley Verified Community Expert]

Might be a test error, a dosing problem, or reduced demand in the tank.

 

[BryanM]

I would double check with another test.

 

[billyocean]

Only 32ml of alk dosed a day in 600 gallons? Am I reading that right?

 

[reefkg22]

Have a large 8ft tank roughly 600G system. I've been battling managing my ALK for the last several months. I use a Neptune Trident to dose 32ML ALK / 20 ML Calc each day. Goal of keeping my alk at 8.15 +/- 10

ALK is 79 doses every 18 mins rotating .4 mL to .8 mL each time.
Calc is dosing 100 times .2 ML every 14 mins.

For the last 3 weeks it's been consistent 8.1-8.25 which was perfect. This past week I had a huge spike to 10.56 without making any changes to the dosing. Do you think the Neptune pumped to much in or could there be other factors that affect alk?

Coral: I have around 50 torch heads, and maybe 12 of them have bailed out among losing several SPS.
latest ICP test (within last 2 weeks): https://www.triton-lab.de/en/showroom/icp-oes/235442

I ran into something similar where alk would spike even without changing dosing. In my case it ended up being a shift in demand from coral loss, so the same dosing became too much. What helped me was adjusting dosing based on actual consumption instead of a fixed schedule.

 

[ReneReef]

Depending on the concentration of your ALK additive your tank is using 0.04 to 0.14 KH per day. That is basically nothing.

By dosing alone it would take 16 up to 58 days to increase your alkalinity from 8.25 to 10.56.

So, your numbers don’t add up and something in dosing and/or measuring must be going wrong.

Also, this all means that your corals are not or barely depositing calcium carbonate and therefore are not or barely growing.
Your corals having stopped growing and dyeing caused your alkalinity and Ca to rise.