High pH (8.5), lowish Alk (7.5)

artieg1 · Mar 18, 2023

I generally have pH at 8.2 and Alk at 8.0. I have had pH creeping upwards the past month. It sits at 8.45 or 8.5 constantly. I dose BRS 2-part. I stopped dosing Alk for a week and it brought it down pH. I started Alk again and pH is back at 8.5 while Alk is low (for me) at 7.5. How is that possible? Most people have the opposite problem.

lapin · Mar 18, 2023

https://reefkeeping.com/issues/2005-03/rhf/

Read the part about adding vinegar

ReefHunter006 · Mar 18, 2023

IMO your going to create more work for yourself trying to control it rather than just letting the tank do what it does.

I run a similar set up on my tanks.

102ttran · Mar 18, 2023

when is the last time you calibrate your ph probes? i really wish to have my ph that high im running kalkwasser and co2 srubber and still got highest 8.25 and low 8

bushdoc · Mar 18, 2023

artieg1 said:
I generally have pH at 8.2 and Alk at 8.0. I have had pH creeping upwards the past month. It sits at 8.45 or 8.5 constantly. I dose BRS 2-part. I stopped dosing Alk for a week and it brought it down pH. I started Alk again and pH is back at 8.5 while Alk is low (for me) at 7.5. How is that possible? Most people have the opposite problem.

BRS 2 part is Calcium chloride and Sodium carbonate ( Soda ash).
I suggest changing to Sodium Bicarbonate it doesn't raise pH, but it raises alkalinity.

sergifed91 · Mar 18, 2023

i had the same issue with 8.55 ph. day time its 8.2 and at night its at 8.55 for ph. but since my house is a older house made in the 40's it still has the original windows which are not energy efficient. especially in the basement. the wind has been horried at night. so i just chalk it up to the poor windows and the draft from the wind going through the old windows. i do have a meter that reads the co2 in my basement and it is usually around 1200. the past three days the readings for my basement is around 400. this normally isn't normal but with the wind being as bad as it has been for the past three days. im not going to worry about it. cause it's just temporary. If i see its effecting my corals and fish in a negative way then i'll worry about it.

Coinzmans Reef · Mar 18, 2023

When something seems off I try to use other testers to back up the results. ICP, Hanna and Red Sea are my go to brands. Usually I need to come to a mean result between multiple tests. The day I send out the ICP the parameters on the Apex are notated for comparison. I put more faith in the ICP than the other test kits due to the variable... (Me)

Randy Holmes-Farley · Mar 19, 2023

FWIW, pH 8.5 is fine. If the alk is 7 dKH, more aeration will lower that pH, if that is a goal.

artieg1 · Mar 19, 2023

Randy Holmes-Farley said:
FWIW, pH 8.5 is fine. If the alk is 7 dKH, more aeration will lower that pH, if that is a goal.

Thanks! It has not gone above 8.5 ever, but that just seemed high based on reading. What is the highest you'd want to see sustained pH? Thanks Randy!

Randy Holmes-Farley · Mar 19, 2023

artieg1 said:
Thanks! It has not gone above 8.5 ever, but that just seemed high based on reading. What is the highest you'd want to see sustained pH? Thanks Randy!

The primary known drawback to pH rising is accelerated precipitation of calcium carbonate on heaters, pumps, etc.

My tank ran pH 8.3 to 8.55 for years and I was not concerned about it.

Yanir34 · May 3, 2023

Randy Holmes-Farley said:
The primary known drawback to pH rising is accelerated precipitation of calcium carbonate on heaters, pumps, etc.

My tank ran pH 8.3 to 8.55 for years and I was not concerned about it.

How does accelerated precipitation of calcium looks like ?