Low PH nightmare

[dbrown4183]

I have never run into this before and hope someone in this group has.

My alkalinity is consistently between 10.26 and 12. My Salinity holds between 36 and 38 depending on where in the water change cycle. Though top offs tend to keep it right around 37.1. My Calcium levels stay between 400- 460

My problem is PH. No matter what I try it raises to around 8.1-8.3 when I put in seachem reef buffer but then drops to 7.71 in around 12 hours.

We have tested the CO2 in the house air and it is low. The CO2 calculator based on carbon hardness, Alkalinity, ph, salinity and temperature seems to also indicate CO 2 isn’t the issue

We have tried everything and our latest experiment was taking out some of the real reef reef rock (I believe that was the brand) and putting it in a container of water change water made from RO/DI water and Red Sea Reef builder salt mix. Over night the rock has appeared to drop the ph in the test water. Is this possible. Has anyone else run into new rock causing the ph to crash?

This is a new tank approximately 4 months old. I am currently trying to add different rock and slowly pull out the old but it seems crazy to me.

I am by no ways new to the hobby as I have kept both saltwater and freshwater tanks for over 40 years but I am also in no way an expert and learn new things all the time from people like you.

Please any suggestions or thoughts would be greatly appreciated.

 

[Randy Holmes-Farley Verified Community Expert]

Reef buffer is a poor choice to boost pH since it boosts alk quite a bit.

Are you tracking alkalinity?

 

[dbrown4183]

Reef buffer is a poor choice to boost pH since it boosts alk quite a bit.

Are you tracking alkalinity?

Yes it hovers between 10 and 12 based on the time after buffering

 

[dbrown4183]

Yes it hovers between 10 and 12 based on the time after buffering

We follow it all with an apex and verifying with liquid tests

 

[Miami Reef]

What pH kit are you using?

 

[p1u5h13r4m24]

I use kalkwasser. I also have a line from my skimmer ran outside. I also put in a fresh air exchange in my house. My ph still drops to 7.8 at night and I’ve calibrated the probe. Got new probes. I just don’t see how anyone can maintain high ph at night.

 

[dbrown4183]

What pH kit are you using?

We are using the apex probe, the api test kit and a Hanna probe to check each other as we we’re hoping the probe was wrong at first but they all are very close to each other

 

[dbrown4183]

I use kalkwasser. I also have a line from my skimmer ran outside. I also put in a fresh air exchange in my house. My ph still drops to 7.8 at night and I’ve calibrated the probe. Got new probes. I just don’t see how anyone can maintain high ph at night.

The problem we have is it doesn’t come back up during the day. If it only dropped at night a large Refugium at alternate hours might help with that.

 

[p1u5h13r4m24]

I found that over feeding will cause lower ph. But I dose my kalk at 8:30’right before lights come on. C02 scrubbers will help if you can’t run ur skimmer line outside

 

[56longroof]

I use kalkwasser. I also have a line from my skimmer ran outside. I also put in a fresh air exchange in my house. My ph still drops to 7.8 at night and I’ve calibrated the probe. Got new probes. I just don’t see how anyone can maintain high ph at night.

My ph runs right at 8.0 at night and 8.2-8.3 for the daytime high. I had to start dosing kalk in the ATO to get there.

 

[ReneReef]

The problem we have is it doesn’t come back up during the day. If it only dropped at night a large Refugium at alternate hours might help with that.

What is your lighting situation?

What are the dimentions for your tank? Which lights do you have (make and model)? How have you programmed them (channel intensities and duration)?

 

[Miami Reef]

We are using the apex probe, the api test kit and a Hanna probe to check each other as we we’re hoping the probe was wrong at first but they all are very close to each other

What pH calibration packets are you using to calibrate the Apex?

 

[dbrown4183]

The lighting is the Red Sea Reef LED 90 that came on the 45 gal set up it is on approximately 12 hrs per day

 

[dbrown4183]

What pH calibration packets are you using to calibrate the Apex?

The ones that Apex provided

 

[dbrown4183]

What is your lighting situation?

What are the dimentions for your tank? Which lights do you have (make and model)? How have you programmed them (channel intensities and duration)?

Tank is the Red Sea 170 which is basically a 45 gal tank with a cube shaped 40 gallon display.

 

[Reginald Reefer III]

Reverse cycle refugium with a ton of chaeto + a CO2 scrubber with good media keeps my pH 8.1-8.3 at all times, even at night.

 

[Miami Reef]

The ones that Apex provided

Take a cup of water and use an airstone outside and heavily aerate the cup for an hour. Measure the pH of the cup using the Apex probe.

Then take the same cup and preform the test inside the house.



1) If the pH doesn’t increase outside, it means something is wrong with the probe.

2) If the pH increases outside, but decreases inside, the issue is excess indoor CO2.

3) If the pH increases outside AND inside, it means the tank itself has low pH, and increasing aeration will solve the issue.

If your result matches number 3, it might also be from the rock. Let us know.

 

[ReneReef]

The lighting is the Red Sea Reef LED 90 that came on the 45 gal set up it is on approximately 12 hrs per day

If that light runs all channels 100% for 6 of the 12 hours. That may be enough lighting.

A lack of pH increase during the day is a sign of too little light. Because: light=photosynthesis=CO2 consumption=pH increase.

 

[dbrown4183]

Take a cup of water and use an airstone outside and heavily aerate the cup for an hour. Measure the pH of the cup using the Apex probe.

Then take the same cup and preform the test inside the house.



1) If the pH doesn’t increase outside, it means something is wrong with the probe.

2) If the pH increases outside, but decreases inside, the issue is excess indoor CO2.

3) If the pH increases outside AND inside, it means the tank itself has low pH, and increasing aeration will solve the issue.

If your result matches number 3, it might also be from the rock. Let us know.

Will do thanks

If that light runs all channels 100% for 6 of the 12 hours. That may be enough lighting.

A lack of pH increase during the day is a sign of too little light. Because: light=photosynthesis=CO2 consumption=pH increase.

thank you I will try that as well

Take a cup of water and use an airstone outside and heavily aerate the cup for an hour. Measure the pH of the cup using the Apex probe.

Then take the same cup and preform the test inside the house.



1) If the pH doesn’t increase outside, it means something is wrong with the probe.

2) If the pH increases outside, but decreases inside, the issue is excess indoor CO2.

3) If the pH increases outside AND inside, it means the tank itself has low pH, and increasing aeration will solve the issue.

If your result matches number 3, it might also be from the rock. Let us know.

we tried exactly what you said and the ph rose outside as expected but when we did it inside it dropped. You are a genius. We had previously checked the co2 numbers inside and they looked good inside the house but they must be high enough that they are affecting the ph in the tank. We ran a line from the protein skimmer outside and also put an airstone from a line outside in the sump and the ph in the tank is rising. Thank you so much for the help. I was about to rip my hair out. I couldn’t believe the rock could be causing the problem after months in the tank but I was at my wits end. Thank you again