I have had PH over 8.5 to 8.7 all week?

[ppht]

I have had high PH all week all day. I have read the docs on it over and over. I have tried the Carbonated water and yes it lowers it fine. But within 2 hrs it's back up. Should I be doing it every day to stabalize? I did have real high nitrates at 50 but I dont have hard corals and have seen people post they had higher for longer periods of time. The only thing I have changed is stronger lights. MH's 2 250w 14k's. So is the brighter lights making my daily PH higher? Is it okay? What else should I do?
Thanks

[rigleautomotive]

do you have a lot of macro algae .if so harvest most of it.same goes for hair algae.clean overflows.do 30 percent water change with rodi water.aged and aerated.that should help i hope.

[Billybeau1]

Did this just start ? What has your pH been say over the last month ?

Can you tell us how you are measuring pH ?

[Randy Holmes-Farley]

What is the alkalinity?

I should point out that unless you are overdosing on limewater, 95% of high pH "problems" are simply pH measurement problems, and the pH really is lower. I am especially inclined to think that if the pH came rapidly back up after CO2 addition.

How are you measuring pH?

[ppht]

I am measuring with AC3 PH probe, Also Red Sea Marine Lab test kit. My ALK is 1.7. I also recalibrated my PH yesterday and the PH went back to around the same readings. I will say I woke up this morning and in the AC logs see my PH dove down to as low as 7.8 This morning it is back to 8.28. I have retested the ALK now and it is at 2.0.

Question: In the natural tank cycle does PH spike? I have had another time in my logs were PH went up to 8.53 never 8.67. But is that possibly part of my tanks peak or bloom for lack of a better word?

Also Randy I would like to thank you for all the great docs you have written and the time you spend helping others. I feel I have the best reference library that anyone could have in a moments notice. Thanks my fellow MA. Native!! lol

[Randy Holmes-Farley]

No, pH does not spike during cycling. It will rarely/never get above about pH 8.5 or so without using limewater. I've never heard of a tank go from pH below 8 to pH above 8.5 in one day without dosing something. If that is real, it is a sign of poor aeration. Complete aeration will keep the pH steady.

Some pH meter are susceptible to electrical interference from nearby ballasts, etc. If you see the pH very high, or jumping around, try measuring the pH in a cup of tank water in another room.

Randy I would like to thank you for all the great docs you have written

Thanks very much. I appreciate it. :)

[ppht]

I have nothing doesing, I unplugged my lighting to see if it was causing an interference but it didnt. I can turn on the Aeration in my flow heads if you think that will help?

Okay correction:
I did get an Aquacontroller Alarm for that low PH. But I just went through all the log times. It never went below 8.22 as far as my hourly log shows... So I dont know what happened there...

[Randy Holmes-Farley]

OK, more aeration might help, and it may also be a calibration error.