How to lower PH

[MichaelP]

Hi

I am having trouble with an overly high ph in my tank. My PH is consistently between 9-9.2. (9 at night and 9.2 during the day)

I though it was my ph probe was slowly going out of sync but just double checked it against a regular test kit and calibrated the probe and am still getting ph in that range.
The tank is a 40 breeder with a large fuge which runs opposite the main tank lights. No skimmer but am running GAC. The tank has only been setup for about 4 months but all of the livestock came from my 150g which I broke down and I never had a problem with high PH there.

for dosing I dose BRS 2 part 20 ML a day and AlK is kept around 7.

many suggestions of what I can do to lower PH and keep it in an acceptable range?

 

[mdb_talon]

I would be very suspicious of any reading that high. I would double check your salinity and alkalinity for starters(and triple check ph).

Otherwise your best best is adding aeration to the tank. Assuming all parameters are truly in range you need more co2 in there and aeration will do that.

Acids can lower it but rarely if ever needed in reef tank as far as i am aware if you have proper parameters and aeration

 

[Darren in Tacoma]

Here is a good thread regarding ph, alk and co2. It sounds like your ph or your alk results are incorrect.

https://www.reef2reef.com/threads/aquarium-ph-distilled.853474/

 

[MichaelP]

Thanks that’s a good read. I didn’t think of the alk test kit being off as well. I did get a 3rd ph test and it also reading high maxed out at 8.8
I am going to bring a sample to my lfs for testing.
And in the mean time switch 2 part dosing to the recipe with sodium bicarbonate that way it’s a slight lowering of ph when dosing vs. raising

 

[Randy Holmes-Farley Verified Community Expert]

That pH is not correct, and unless you are dosing hydroxide additives for alkalinity without good aeration, I do not think any reefers will have pH high enough to warrant action to lower it (pH 8.6 or higher).

 

[Reefer750Tx]

Hi

I am having trouble with an overly high ph in my tank. My PH is consistently between 9-9.2. (9 at night and 9.2 during the day)

I though it was my ph probe was slowly going out of sync but just double checked it against a regular test kit and calibrated the probe and am still getting ph in that range.
The tank is a 40 breeder with a large fuge which runs opposite the main tank lights. No skimmer but am running GAC. The tank has only been setup for about 4 months but all of the livestock came from my 150g which I broke down and I never had a problem with high PH there.

for dosing I dose BRS 2 part 20 ML a day and AlK is kept around 7.

many suggestions of what I can do to lower PH and keep it in an acceptable range?

I just heard that baking a cheesecake will help bring down the pH. (Due to the access Co2) …if nothing else, along with a glass of milk, it sure will help cheer you up : ). Good luck!

 

[Rob3D2018]

That pH is not correct, and unless you are dosing hydroxide additives for alkalinity without good aeration, I do not think any reefers will have pH high enough to warrant action to lower it (pH 8.6 or higher).

@Randy Holmes-Farley
Hello Randy, I am having a similar issue as the OP. Your comment above prompted me to check the powder I use to dose kalkwasser. It is from BRS and it says they use calcium hydroxide to make the powder.

Is there anything without the hydroxide part that I can use? My pH is 9.3-9.8 and everything looks good and healthy.
Is there a build-up of this hydroxide if the tank does not undergo water changes for a year and a half?

Thank you for taking the time to answer my post.

 

[Randy Holmes-Farley Verified Community Expert]

@Randy Holmes-Farley
Hello Randy, I am having a similar issue as the OP. Your comment above prompted me to check the powder I use to dose kalkwasser. It is from BRS and it says they use calcium hydroxide to make the powder.

Is there anything without the hydroxide part that I can use? My pH is 9.3-9.8 and everything looks good and healthy.
Is there a build-up of this hydroxide if the tank does not undergo water changes for a year and a half?

Thank you for taking the time to answer my post.

I think that must be a testing error, or a typo. Seawater is not stable at pH 9.8, and precipitates will rapidly form.