As I mentioned in another thread I started a few weeks ago, I have a renewed interest in my 75 gallon reef tank. (Well, I say reef tank but it only has one coral left atm)...Today I did some water tests and my PH was 7.3 so, it's a nice day here with a little breeze so I opened the windows. A couple of hours later I checked PH and it was 7.2...That doesn't make sense to me. Admittedly, I'm using a no name PH probe because even though I ordered all new Red Sea test kit refills, I forgot to get a PH test kit...But still, even if the hand held probe isn't accurate, shouldn't it have gone up with the windows open? The only things I'm running on this tank are a Reef Octopus HOB skimmer and a dual BRS carbon/gfo reactor which currently has only carbon running in one chamber, the other is empty...If it matters, the light intensity was brighter for the second test...Thanks in advance...
PH Question
- Thread starter Razz
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Every time u test your ph it won’t be the same. Up and down all the time just keep in range 7.3 is Low. At less 7.6 easy way to fix u can get a tube pull fresh air in your skimmer. Will helps increase ph. Here is a pic show u how ph moves on my apex
Best way is run a line. Or. The money way is co2 reactors but cost too much money won’t recommend. U can test the ph next day u will see increasing
Randy Holmes-Farley
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Have you measured the alkalinity? If it is anything close to normal or higher, a pH of 7.2 is testing error. 
Have you measured the alkalinity? If it is anything close to normal or higher, a pH of 7.2 is testing error.
Good call!
Ok, thanks...I'll try running a line outside and see if it helps. BTW, I looked around and found the box for the probe. It's an HDE brand...anyone have any experience with them? Yes, I checked alk with a Hannah Checker and it's at 8.176 dkh...guess the probe is at fault...Thanks guys!
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Did you recently calibrate the pH meter? If not, do that before bothering to do anything else.
Did you recently calibrate the pH meter? If not, do that before bothering to do anything else.
I think he say he use redsea test kit not probe
No, I didn't calibrate it. Is there an easy way? The instructions say to use a standard ph 6.86 phosphate buffer solution then adjust the probe. Then use a standard ph 4.01 borax buffer solution and wait for 1 minute and the value should be shown...I have no idea how to make these solutions...
U have to calibrate it. Before when I start use apex didn’t calibrate. My ph was showing 7.4-7.6. After dos kalkwasser. Lost few coral. Them found out calibrate. Soo I did learn the hard way
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Much more common is to buy standards, usually pH 7 and 10 when measuring pH above 7. It might or might not be worth measuring pH, but it isn't worth doing without calibrating it.
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These have more:
pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/
Aquarium Chemistry: Measuring pH with a Meter
https://www.advancedaquarist.com/2004/2/chemistry
pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/
Aquarium Chemistry: Measuring pH with a Meter
https://www.advancedaquarist.com/2004/2/chemistry
Here is form brs calibrate https://www.bulkreefsupply.com/milwaukee-ph-calibration-fluid-single-use-packet.html
You are 100% correct, testing without calibrating is pointless but I only used it a few times and assumed it was at least close from the factory, my mistake...I know better than that...anyway, thanks for the links, I will check them out!
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Ok, I just read thru the first article you linked...There's alot of good info there, I'm going to have to read it a few more times to grasp it all...lol...Once again, thanks for the info!!
