If its not CO2, then why low pH

[DrZoidburg]

It could really be a number of things. It could be bacterial. Usually anaerobic bacteria. Like in a deep sand bed or sulfur reactor. C02 for example will lower ph but not affect alkalinity until lower than 5 ph ish. More what I was thinking adding acidic dose, or anything acidic. Rodi water after resins sometimes acidic, in mine it comes out at ph 5. Gases, amino acids, bunch of things. Along with something like boron or other things that add to alk that is not being used as fast as you dose it. Keeping ph in a down trend while alk staying the same. Same thing until a certain ph for other organic acids, formate, acetate...etc, and conjugate bases. Only thing I think other than aeration that could help quickly would be to buffer the dose container with something basic to get dose over 7-7.5 ish. Would take a drop or two of sodium carbonate, or calcium hydroxide, some playing around with ph meter to get it there. Some dilute acid if you over shoot and get precipitation. Also check rodi output. I use a old carbon reactor filled with aragonite to buffer it. Ph 5 in about 9 out. Will definitely take some troubleshooting.

 

[DrZoidburg]

To add it seems to happen at night according to apex chart. I likely think its is a mix of all things not just C02. Like randy said about air exchange being slow for CO2. This is true because the vapor pressure is much lower than O2. If your using big air exchange and its not raising as much as you want. Not over 8.01 you said which is surprising. It would suggest that their is something acidic also. It might require a creative mix of solutions. Buffer anything going in, and run the air exchange more at night, algae reactor at night.

 

[Randy Holmes-Farley]

So turns out their k+ does not stand for potassium stands for cation..

It's one of my all time favorite reef hobby names:

The product "K+ Elements" does not actually contain the element K+. lol

 

[Lasse]

It's one of my all time favorite reef hobby names:

The product "K+ Elements" does not actually contain the element K+. lol

The K+ stands for the german Kation and the A- stands for the german Anion - in english it means Cation (a positive charged ion) and Anion (a negative charged ion) - its not more complicated than that.

Sincerely Lasse

 

[Randy Holmes-Farley]

The K+ stands for the german Kation and the A- stands for the german Anion - in english it means Cation (a positive charged ion) and Anion (a negative charged ion) - its not more complicated than that.

Sincerely Lasse

Yes, I know. Lou explained it once as I told him it was a crazy name.

It's still crazy. lol

 

[DrZoidburg]

Yes, I know. Lou explained it once as I told him it was a crazy name.

It's still crazy. lol

i was thinking it stood for kalium

 

[Biologic]

To add it seems to happen at night according to apex chart. I likely think its is a mix of all things not just C02. Like randy said about air exchange being slow for CO2. This is true because the vapor pressure is much lower than O2. If your using big air exchange and its not raising as much as you want. Not over 8.01 you said which is surprising. It would suggest that their is something acidic also. It might require a creative mix of solutions. Buffer anything going in, and run the air exchange more at night, algae reactor at night.

I’m actually going to get a larger protein skimmer a Deltec MCE 601 which pulls in more air. 400 liters per hour VS my current 150.

I did see a large increase of pH when I brought it outside. 1) when I aerated the water, pH shot up to 8.23 easily 2) when I performed the same aeration test with a CO2 scrubber, outside, the pH shot up to 8.52.

I did the same test again indoors, the pH actually did rise a bit during the day which tells me CO2 is higher at night.

The K+ stands for the german Kation and the A- stands for the german Anion - in english it means Cation (a positive charged ion) and Anion (a negative charged ion) - its not more complicated than that.

Sincerely Lasse

Ah I knew that makes since!

 

[josephxsxn]

I did the same test again indoors, the pH actually did rise a bit during the day which tells me CO2 is higher at night.

During the day your experiencing the photo period as such co2 is being consumed by the organisms in the tank that are performing photosynthesis.

Unless you're saying you did an aeration test with no organisms in it?

 

[Biologic]

During the day your experiencing the photo period as such co2 is being consumed by the organisms in the tank that are performing photosynthesis.

Unless you're saying you did an aeration test with no organisms in it?

Correct, I do experience a pH increase throughout the day and a swing at night, which I know is normal. I am trying to minimize the low swing.

I did an aeration test that was outside in an erlenmeyer beaker. There is excess CO2, but from where? It’s easy to passively say, it’s from inside the house. Which I will be going on vacation for several days and that theory will be put to the test. I am not convinced until I get my CO2 meter that shows a huge difference between outside and inside.

I think it’s biotic processes driving low pH. The inside CO2 is only a smaller portion of the problem.

I am going to repeat the CO2 aeration test again, because I got different results last time than my first test.

Getting a larger skimmer and continuing pulling outside air or even inside air should increase my pH significantly. At least the CO2 will be at equilibrium to what’s in the environment inside the home or outside the home.

 

[Biologic]

Look at this lovely ball of bacteria floating around the tank.

 

[Randy Holmes-Farley]

I did an aeration test that was outside in an erlenmeyer beaker. There is excess CO2, but from where? It’s easy to passively say, it’s from inside the house. Which I will be going on vacation for several days and that theory will be put to the test. I am not convinced until I get my CO2 meter that shows a huge difference between outside and inside.

I think it’s biotic processes driving low pH. The inside CO2 is only a smaller portion of the problem.

I am going to repeat the CO2 aeration test again, because I got different results last time than my first test.

Getting a larger skimmer and continuing pulling outside air or even inside air should increase my pH significantly. At least the CO2 will be at equilibrium to what’s in the environment inside the home or outside the home.

Did you get a pH difference aerating inside and out?

 

[Lasse]

​

Outside CO2 is around 400 - 420 ppm. Here you can see my indoor CO2 las week - 2 persons + a cat- It will be a lot

Todays figures

Sincerely Lasse

 

[Croftsy]

Hi I was reading this post as I m also looking put an outside air pipe feed to my skimmer I m just not sure where it goes to on my skimmer. If anyone could help that would be great (see photo) can I take the blue pipe off and go directly into where I marked “2”? Or do I feed it in the red cap in “1”
Thanks

 

[josephxsxn]

Hi I was reading this post as I m also looking put an outside air pipe feed to my skimmer I m just not sure where it goes to on my skimmer. If anyone could help that would be great (see photo) can I take the blue pipe off and go directly into where I marked “2”? Or do I feed it in the red cap in “1”
Thanks

I took the part#1 off my skimmer and put it at the end of my hose outdoors which then goes directly to #2. I am not feeding the little red cap.

 

[Croftsy]

I took the part#1 off my skimmer and put it at the end of my hose outdoors which then goes directly to #2. I am not feeding the little red cap.

So you still used the blue hose and basically jointed the pipe at part 1. Did you have to do anything to the little bottle that has the red plug on or just left it as it doesn’t have anything to do with the skimmer anymore. Did you find it worked week when you don’t that to yours?

 

[Lasse]

The bucket is a silencer (inside black circle) - you should connect your outside air to the nipple in the red circle- if they are two - take two tubes and connect them to the outside air tube

Sincerely Lasse

 

[RobB'z Reef]

Some good testing. So it seems to be high co2 in your house. Keep in mind the more agitation on the surface water will add more co2 to the tank as was stated. A bigger skimmer with outside air should help. I can only say this because I had the same issue. I had 7.8 - 7.9 with inside air to my skimmer. Plumbed a 3/4" pvc pipe to outside air(only about 10 feet with 1 elbow) and ph rose to 8.0 - 8.05. Next I added a co2 scrubber (di resin canister with 1/2" ports) and the ph is now 8.15 - 8.25. My house is pretty sealed and loaded with kids and animals. Well the kids do unseal the house with the freaking doors always opening. Ha!! Also it took about 2 days to see the ph change after each test. As someone stated the air line can't be too small or it will choke the skimmer. The main reason why I say maybe you need a bigger skimmer is because with a smaller skimmer my ph slightly rose from 7.8 to maybe 7.83. I use a simplicity dc240 for a 125 gallon tank and my alkalinity is 9.7. I do dose kalkwasser via an ato to maintain alkalinity and calcium and do a 15% water change weekly. Hope this helps you a bit.

Plumbed a 3/4" pvc pipe to outside air(only about 10 feet with 1 elbow) and ph rose to 8.0 - 8.05.

Can you elaborate on this a bit? How did you tie this into your setup? I'm pulling outside air via a 3/8" silicone tubing but my run is nearly 20' long to get there and I'm thinking it affects the draw (even more so in the humid summer). I've often wonders if there would be a way to integrate some sort of air pump to actively draw the air from outside to assist the skimmer venturi.

 

[josephxsxn]

So you still used the blue hose and basically jointed the pipe at part 1. Did you have to do anything to the little bottle that has the red plug on or just left it as it doesn’t have anything to do with the skimmer anymore. Did you find it worked week when you don’t that to yours?

I used to try and adjust the silencer as it does impact the skimmer if closed off but anymore I leave it full open and have gotten better skimmer performance by raising it higher in the sump agaisnt the water level (put a upside down bowl under it to lift the skimmer about 4 inches.) Didn't use the original tubing and just bought more of the same ID, it travels probably 20-30' I forget the exact distance, see pics... Coming out my window for now and to my bedroom deck. One day I'll make a better exit location then the window (which I stuff so that it's still weather tight.)

 

[capted]

Can you elaborate on this a bit? How did you tie this into your setup? I'm pulling outside air via a 3/8" silicone tubing but my run is nearly 20' long to get there and I'm thinking it affects the draw (even more so in the humid summer). I've often wonders if there would be a way to integrate some sort of air pump to actively draw the air from outside to assist the skimmer venturi.

I ran a pvc pipe right through the house! It's behind the tank so you don't see it in the house. I got lucky with that. If I ever move the tank then it will be a problem. Put an adapter on the end of the pipe for a 3/8" silicone hose that goes to my co2 scrubber then to my skimmer air inlet with a valve if I need to control air flow. Pics not so good but shows what I mean. Going on almost 2 months for the co2 media and it's just starting to exhaust. Also the scrubber has 1/2' ports for more airflow. Oh and I glued some window screen to the outside elbow to keep bugs out of the line.

 

[Croftsy]

photos make it so much easier I’ve temporarily linked a hose up from skimmer to outside now will make it properly over weekend. How long till you see any results hours/days/weeks or months