How can I raise pH without spiking Alk?

[maxemorris]

I tested my water and my pH was 7.4, super low. My water is really clean, and I do 20% water changes every week with zero ammonia nitrite or nitrate (I recently started feeding heavier and adding reef roids to raise nitrates).

Is there anyway to raise my pH without adding a buffer? My alk was around 9.8 before adding buffer, and now it’s 20!! I’m doing a water change now to fix it, but what can I do next time? Thoughts on Aragonite media?

I do water changes with RODI water and Fritz RPM salt mix.

 

[maxemorris]

I tested both parameters twice to make sure

 

[Garf]

now it’s 20!!

That is high, lol;

http://www.reefkeeping.com/issues/2004-09/rhf/index.htm

 

[Randy Holmes-Farley]

If this is a reef tank, I do not believe it is accurate, no matter how many times you tested it.

Calcium carbonate dissolves at pH 7.4.

Never add buffers to raise pH. The effect is exactly what you observe: excessive alk.

 

[maxemorris]

If this is a reef tank, I do not believe it is accurate, no matter how many times you tested it.

Calcium carbonate dissolves at pH 7.4.

Never add buffers to raise pH. The effect is exactly what you observe: excessive alk.

I am in disbelief myself, but this is my third test and I have used the checker many times with accuracy. Do you have an alternative to adding buffer?

 

[maxemorris]

I’m doing a large water change now to bring down the alk but I expect to encounter low pH again, is there an alternative solution to buffer?

 

[Randy Holmes-Farley]

I am in disbelief myself, but this is my third test and I have used the checker many times with accuracy. Do you have an alternative to adding buffer?

I know you have little reason to know me to trust me in this, but the pH is wrong. All sorts of things can go wrong.

What are you using to measure pH? How did you calibrate it?

Of course there are ways to raise pH. A buffer is NEVER the best choice.

Since alk is high, you cannot use a high pH alk supplement, so you have to reduce pH in other ways, such as more fresh air to the room, a CO2 scrubber, outside air to a skimmer inlet, and more photosynthesis such as with a refugium.

 

[maxemorris]

I know you have little reason to know me to trust me in this, but the pH is wrong. All sorts of things can go wrong. If you want to measured pH, get a meter. Those are easily calibrated and checked. The Hannah is not.

Of course there are ways to raise pH. A buffer is NEVER the best choice.

Since alk is high, you cannot use a high pH alk supplement, so you have to reduce pH in other ways, such as more fresh air to the room, a CO2 scrubber, outside air to a skimmer inlet, and more photosynthesis such as with a refugium.

Thank you! I had the Ph tested from two separate test kits, but I understand that the liquid tests are more inaccurate. It’s a biocube with a tight lid, so there’s little gas exchange and I think that’s my issue. Someone recommended aragonite media, thoughts?

 

[jda]

Your alk is likley higher than 20. That is just the max, I think. It might come down in the morning if you added the buffer recently once it mixes all the way. There are online calculators that you can use with your gallons and media (carbonate or bicarbonate?) and how much you used to see what the rise might be.

I would get as much fresh air into the home as possible and aerate the tank as much as possible. This will drive off the co2. You can also mix some low alk fresh saltwater with some acid to lower the alk, but this can take days to make and wait for the co2 to dissipate.

Color test kits are not reliable for pH, IMO. A good pH pen or meter is way better.

 

[Randy Holmes-Farley]

Thank you! I had the Ph tested from two separate test kits, but I understand that the liquid tests are more inaccurate. It’s a biocube with a tight lid, so there’s little gas exchange and I think that’s my issue. Someone recommended aragonite media, thoughts?

Having little gas exchange is a poor plan for several reasons. Do you have a skimmer? The tank certainly may need more aeration.

aragonite is not generally very useful for pH raising in a reef tank.

Can you post a picture of the tank? If this is a reef tank, it presumably already has live rock and maybe sand in it? That is typically aragonite.

If the pH was 7.4, simple aeration with outside air will raise it hugely.
Try this test:

pH and the Reef Aquarium - REEFEDITION

by Randy Holmes-Farley For many aquarists, pH is not something that they have much experience with aside from their aquarium. For many, pH is almost a black box measurement: something to be considered, but whose physical meaning makes little sense to them. This article will Read more here...

www.reefedition.com

The Aeration Test

Some of the possible causes of low pH listed above require an effort to diagnose. Problems 3 and 4 are quite common, and here is a way to distinguish them. Remove a cup of tank water and measure its pH. Then aerate it for an hour with an airstone using outside air. Its pH should rise if it is unusually low for the measured alkalinity (Figure 2). Then repeat the same experiment on a new cup of water using inside air. If its pH also rises, then the aquarium’s pH will rise simply with more aeration because it is only the aquarium that contains excess carbon dioxide. If the pH does not rise in the cup (or rises very little) when aerating with indoor air, then that air likely contains excess CO2, and more aeration with that same air will not solve the low pH problem (although aeration with fresher air should). Be careful implementing this test if the outside aeration test results in a large temperature change (more than 5°C or 10°F), because such changes alone impact pH measurements.

 

[maxemorris]

Having little gas exchange is a poor plan for several reasons. Do you have a skimmer? The tank certainly may need more aeration.

aragonite is not generally very useful for pH raising in a reef tank.

Can you post a picture of the tank? If this is a reef tank, it presumably already has live rock and maybe sand in it? That is typically aragonite.

If the pH was 7.4, simple aeration with outside air will raise it hugely.
Try this test:

pH and the Reef Aquarium - REEFEDITION

by Randy Holmes-Farley For many aquarists, pH is not something that they have much experience with aside from their aquarium. For many, pH is almost a black box measurement: something to be considered, but whose physical meaning makes little sense to them. This article will Read more here...

www.reefedition.com

The Aeration Test

Some of the possible causes of low pH listed above require an effort to diagnose. Problems 3 and 4 are quite common, and here is a way to distinguish them. Remove a cup of tank water and measure its pH. Then aerate it for an hour with an airstone using outside air. Its pH should rise if it is unusually low for the measured alkalinity (Figure 2). Then repeat the same experiment on a new cup of water using inside air. If its pH also rises, then the aquarium’s pH will rise simply with more aeration because it is only the aquarium that contains excess carbon dioxide. If the pH does not rise in the cup (or rises very little) when aerating with indoor air, then that air likely contains excess CO2, and more aeration with that same air will not solve the low pH problem (although aeration with fresher air should). Be careful implementing this test if the outside aeration test results in a large temperature change (more than 5°C or 10°F), because such changes alone impact pH measurements.

Thank you again for your thorough replies! I attached a picture of my tank, alongside my test from this morning pH is back down to 7.8 and my DH is down to 16.6 from what I assume was the max the checker would read.

I left a lid open last night and will continue to do so every night, checking salinity for evaporation. Do you think that is enough? I have a return pump and a power head in the tank, giving about 25x turnover.

 

[Estonian Reefer]

Opening windows and letting fresh air in is the best way to raise PH without adding anything

 

[GARRIGA]

I'm just replying to the increasing of ph without a buffer and expanding on what others have mentioned. Because my house is crowded and rather air tight due to new construction and living in a high humidity south Florida environment, house co2 is likely very elevated and can be validated by the fact my ph rises when less people are home. Therefore, skimmer or surface aeration will not likely solve my issue because tank co2 will just increase due to room co2. My one and only remaining solution is a Fuge or ATS. Goal is to allow nature to remove co2 from tank water. Why it's important to first determine what may be causing low ph before making random changes.

As to the high alkalinity, if this was caused by adding buffers and needs to be dropped (assuming tests are accurate and not affected by old regents or need for calibration) then consider using Sodium Bisulphate or Seachem Acid Buffer to slowly reduce that alkalinity by converting it to co2. This will temporarily reduce ph and sounds counter productive but it's what I've used in the past to combat high alkalinity because of something such as using kalk to raise ph which in my case didn't work because of the previously mentioned high amount of room co2.

When in doubt, have a backup test kit. Something such as API can quickly estimate where you're at and doesn't have a max since it's based on number of drops changing color. Because I'm comfortable with 7-11 dkh. This is all I use because as long as it's between 8-10 that ensures I have some cushion due to API not being precise. It's cheap. Readily available. Quick to test. Dummy proof.

 

[maxemorris]

Opening windows and letting fresh air in is the best way to raise PH without adding anything

I’ll do that today!

 

[mangolove]

FRESH AIR or C02 scrubber (filters you air)

 

[maxemorris]

Update: opened all the windows, lid is off, and I even added an aerator to bring more oxegyn to the water. I’m doing another large water change to bring down that alkalinity further. Lesson learned– never use buffer!

 

[maxemorris]

Update: water changes have lowered DKH to a safe number, will the coral consume the alkalinity down further, or do I need another water change?

 

[Randy Holmes-Farley]

I’d let it drop in its own.

 

[maxemorris]

I’d let it drop in its own.

Thank you for all your help! With the weather in FL getting cooler I will keep the windows and the lid open more often, and within the next year I plan to upgrade to a ~50gal rimless tank with an open mesh lid.