Poland Springs Distilled Water: pH 5.5

[Weebay]

Over the past few weeks my pH has been dropping with my Red Sea tests so I ordered an Apera pH 20 off Amazon to see if my readings were accurate. I test my aquarium water and comfirm that the pH of my tank is around 7.6. Confused as to what could be causing this I decided to test my distilled water, a brand that I have been using off an on over the past few months, low and behold.... the pH of this Poland Springs "distilled" water is 5.5! What in the acutal F???!? Somehow everything seems to be doing okay and I have at least discovered the problem, but what the heck. I have a bottle of pH buffer arriving tomorrow so hopefully that will rectify the issue but now I'm not sure what to do as far as my top offs go. I live in a small apartment and don't have room for a rodi system. I guess I will at least avoid Poland Springs in the future and will have to test every jug I buy from now on. Has anyone else had this issue?

 

[Randy Holmes-Farley]

Two issues:

1. No normal pH meter can accurately measure the pH of fully deionized or distilled water. Ions are needed for proper functioning of the device.

2. Distilled water will have pH well below 7 due to CO2 entering it from the air, making carbonic acid and lowering pH.

 

[Randy Holmes-Farley]

Finally, the pH of pure fresh water added to a reef tank is never a cause of low pH

Curiously, if you add pH 7.0 totally pure fresh water to seawater at pH 8.20, the final pH will be above pH 8.20. One cannot simply look that the pH of two solutions to know what the mixed pH will be.

 

[Weebay]

Finally, the pH of pure fresh water added to a reef tank is never a cause of low pH

Curiously, if you add pH 7.0 totally pure fresh water to seawater at pH 8.20, the final pH will be above pH 8.20. One cannot simply look that the pH of two solutions to know what the mixed pH will be.

Amazing! That all makes sense!

But, now I am left wondering what the heck is going on. I may have part of my answer after taking a reading of my Instant Ocean Nutri-Seawater, it is reading 7.6 which is also the pH of my tank. Are there any chemistry considerations I am missing with this water? The reading should be accurate I would imagine since it should have plenty of ions to make the appropriate reading. Does CO2 diffuse into this seawater as well when it is just sitting around?

 

[Randy Holmes-Farley]

Yes, your home air is a big driver of tank pH. A tightly sealed home can result in elevated CO2 and cause low pH.

This has more:

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

 

[Weebay]

Yes, your home air is a big driver of tank pH. A tightly sealed home can result in elevated CO2 and cause low pH.

This has more:

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

Thank you for the article!

I suspect that as the article points out, I must be dealing with either elevated CO2 within my apartment or poor aeration (or both). I typically have the AC running most of the time during the summer months with two large dogs in the apartment so I imagine that could be enough to raise the CO2. I feel like my flow is decent but it's definitely not turbulent by any means, so that is probably also contributing (it's a small tank so I feel like this is probably less of an issue but I have no idea really).

In terms of solving this problem... I don't think any of the options listed for raising the CO2 levels within my apartment would be practical. The product I ordered is AquaVitro eight.four, do you think this will be a viable option (at least in the short term) to raise my pH?

It seems like the most practical long term solution is to to stuff some macroalgae into my tiny AIO sump but I'll need some time to make this happen. Do you think the eight.four solution will be sufficient for the next few weeks while I prepare to get a refugium going? If not, should I start dosing kalkwasser instead?

Thank you for your replies!!