Raising PH and Alk with high magnesium

[Joffunswife]

Hi all. These are my current parameters




I have tested these twice with hanna testers and checked along side salifert tests.
Can anyone recommend how to raise my alk and ph without raising my magnesium any higher. I am uk based and tank is 400l/105 us gal.

Thanks all

 

[rishma]

There are several good ways to supplement alkalinity and simultaneously raise pH, but before going there we need to investigate your values. Both the magnesium and pH values are suspect, with the pH being very unlikely.

How was pH measured?

Have you dosed a lot of magnesium?

 

[Hairyteeth]

You can dose soda ash to raise alk and ph

 

[Joffunswife]

There are several good ways to supplement alkalinity and simultaneously raise pH, but before going there we need to investigate your values. Both the magnesium and pH values are suspect, with the pH being very unlikely.

How was pH measured?

Have you dosed a lot of magnesium?

I have been dosing all for reef to raise the alk which it has done a little but not as much as I expected

 

[Joffunswife]

Also PH was tested with both Hanna checker and Salifert liquid test. My LFS also confirmed all these readings for me too.

 

[rishma]

It would be highly unusual to have pH that low. It would be slowly dissolving your rocks, sand, corals. You would have to dose something acidic or have extreme CO2 levels in your home for that to make sense. Do you have living things in your tank? How is everything doing?.

Regarding magnesium, if you are using all for reef as the supplement then your magnesium is not that high. Magnesium tests kits are so unreliable as to not be worth using at all. Fortunately products like all-for-reef provide magnesium proportional to the alkalinity and calcium so you don’t need to worry about it. This thread is good reference regarding magnesium testing.

https://www.reef2reef.com/threads/just-say-no-to-magnesium-testing-rmm-is-born.1017528/

 

[Joffunswife]

It would be highly unusual to have pH that low. It would be slowly dissolving your rocks, sand, corals. You would have to dose something acidic or have extreme CO2 levels in your home for that to make sense. So you have living things in your tank? How is everything doing?.

Regarding magnesium, if you are using all for reef as the supplement then your magnesium is not that high. Magnesium tests kits are so unreliable as to not be worth using at all. Fortunately products like all-for-reef provide magnesium proportional to the alkalinity and calcium so you don’t need to worry about it. This thread is good reference regarding magnesium testing.

https://www.reef2reef.com/threads/just-say-no-to-magnesium-testing-rmm-is-born.1017528/

We have got naturally extremely low ph water here. The lowest in the UK I believe. It tests at 7.6 from the tap before it goes through the rodi unit. Everything is mostly ok in the tank. Fish are fine, inverts are fine, most corals are fine bar my zoas and polyps but they have been introduced in the last few days so still acclimating and had to have a treatment for hair algae prior to being put in so no doubt they’re a little annoyed.

 

[rishma]

We have got naturally extremely low ph water here. The lowest in the UK I believe. It tests at 7.6 from the tap before it goes through the rodi unit. Everything is mostly ok in the tank. Fish are fine, inverts are fine, most corals are fine bar my zoas and polyps but they have been introduced in the last few days so still acclimating and had to have a treatment for hair algae prior to being put in so no doubt they’re a little annoyed.

Ok, but once the water goes through the RODI and mixed with your salt your pH is governed primarily by CO2 and alkalinity. Even with high indoor CO2 (like 3x outdoor) your pH at 7.5 dKH would be much higher than a pH of 7.3.

I also don’t think your animals would be ok 7.3 pH. It’s way outside the norm.

Dosing more all-for-reef is what I do to increase alkalinity. Dosing all-for-reef to meet my daily alkalinity demand is my preferred approach.

I understand this doesn’t help you raise your pH, but since I don’t believe the value I’m hesitant to recommend anything other than a pH probe or some other method to measure pH.

 

[Joffunswife]

We have got naturally extremely low ph water here. The lowest in the UK I believe. It tests at 7.6 from the tap before it goes through the rodi unit. Everything is mostly ok in the tank. Fish are fine, inverts are fine, most corals are fine bar my zoas and polyps but they have been introduced in the last few days so still acclimating and had to have a treatment for hair algae prior to being put in so no doubt they’re a little annoyed.

Ok, but once the water goes through the RODI and mixed with your salt your pH is governed primarily by CO2 and alkalinity. Even with high indoor CO2 (like 3x outdoor) your pH at 7.5 dKH would be much higher than a pH of 7.3.

I also don’t think your animals would be ok 7.3 pH. It’s way outside the norm.

Dosing more all-for-reef is what I do to increase alkalinity. Dosing all-for-reef to meet my daily alkalinity demand is my preferred approach.

I understand this doesn’t help you raise your pH, but since I don’t believe the value I’m hesitant to recommend anything other than a pH probe or some other method to measure pH.

The Hanna checker we use is the red probe version. My LFS also use a prob all though there’s is more ‘advanced’ than our Hanna tester

 

[Randy Holmes-Farley Verified Community Expert]

We have got naturally extremely low ph water here. The lowest in the UK I believe. It tests at 7.6 from the tap before it goes through the rodi unit. Everything is mostly ok in the tank. Fish are fine, inverts are fine, most corals are fine bar my zoas and polyps but they have been introduced in the last few days so still acclimating and had to have a treatment for hair algae prior to being put in so no doubt they’re a little annoyed.

The pH of the source water before the ro/di is unimportant if you are getting it to 0 ppm tds.

 

[rishma]

I understand the inclination to trust the pH measurement but it would indicate extreme indoor CO2 levels and no mitigation from photosynthesis. Not impossible, but unlikely.

When do you last calibrate your pH probe?