Why is alk high?

[jacobcoral]

I’ve never had my alk so high especially without dosing anything. I havnt tested this water in awhile and its just had rocks and 2 clowns. Is it because there was no coral depleting it?

Alk 11.8

Nitrate 6.5

Phos .08

 

[Miami Reef]

That’s a potential contributing factor.

This short article shows the most common reasons why alkalinity can rise despite not dosing it:

https://www.reef2reef.com/ams/the-ways-alkalinity-can-accumulate-in-a-reef-tank.902/

 

[Amstar]

what type of salt do you use? when was your last water change vs the time that you did your test?

 

[jacobcoral]

what type of salt do you use? when was your last water change vs the time that you did your test?

Water change had been awhile. I use Red Sea blue bucket

 

[BryanM]

I’ve never had my alk so high especially without dosing anything. I havnt tested this water in awhile and its just had rocks and 2 clowns. Is it because there was no coral depleting it?

Alk 11.8

Nitrate 6.5

Phos .08

Have we ruled out test error just in case? I always do a 2nd test after a result that has me concerned just to make sure it was in the ballpark.

 

[Amstar]

what are you using to test alk (which tester) - have you been able to cross check it against another tester