Does Instant Ocean Lower the PH?

[Amazon4]

Hi,

We've found the Instant Ocean lowers our PH right out of the box. We have to raise it before we add it to our tank.

Our waters PH is 8.7 to start. Then we add the salt mix, and it drops to mid 7's. Is this normal?

So, to use this stuff we add calcium and raise the PH. Is there not a better way? Is there a better mix, more suited to a reef tank, to use?

[serpentman]

It shouldn't lower it too much. You might try a reef mix. However, IMO, your pH is way too high. I would shoot for 8.2-8.4

[David Grigor]

Are you saying the RO water before adding the mix is 8.7 ? or the tank PH is 8.7 ?

[Randy Holmes-Farley]

[welcome]

Hey Amazon4, we live in the same town!

FWIW, the pH that you get after aerating new salt water depends on the alkalinity in it (IO has plenty) and the CO2 in your home air. If after mixing the pH is too low, and the pH measurement is accurate, blame your air.

This article has more:


Low pH: Causes and Cures
http://reefkeeping.com/issues/2004-09/rhf/index.htm

[Amazon4]

My bad..the starting water is 8.7. Our tank water is 8.05 (working on raising it).

[Amazon4]

Hi Randy,

We got to hear your talk at the BRS meeting a couple of weeks ago. On your advice we added an air stone to the tank. It has helped - thanks!

But what we found odd was that if we take a bucket of FW at 8.7 and add IO, the PH immediately drops. Is that the chemistry of the OI? Or do you think it's the air?

We got a new digital PH meter, so we're confident of our readings.

Our RODI shows up today. Looking forward to using RODI water (yes...guilty of using tap water from Arlington...)

[Randy Holmes-Farley]

The pH of the mix should be lower than 8.7, so the effect you see is normal. When you get it, the pH of the RO/DI water may still read high (mine does, although I'm not sure if that is real or an artifact of the very large difficulties associated with measuring the pH of very pure water), but that has little effect on the pH after mixing with salt and aerating.