Best time to check PH?

[GQ22]

I started dosing two part the other day and last night @ 10 right after my halides turned off, I decided to check my PH as earlier in the morning before i left i had added a portion of CA and ALK.

My reading was 8.8 for PH @ the moment. Since it was high i dosed a portion of Magnesium. My system is deficient in Magnesium anyway and this was only the second time ever i dosed magnesium into it.

The next morning i tested my PH with all the lights off @ 7 AM and the PH was 8.0

Is this b/c of the time of day and lights or lack of light causing this PH swing or can it be the new addition of Two Part?

What is the best time to test PH for a reliable reading?

 

[marrone]

It's very common for the Ph to drop after the lights go off and some times it will fall below 8.0. You Ph of 8.8 seems high what is your Alk reading? The high reading could be from putting to much of the Alk part in.

Here a link on Ph that really go into explainning all the changes and swings.
http://www.reefkeeping.com/issues/2005-03/rhf/index.php
http://www.advancedaquarist.com/issues/feb2004/chem.htm

I generally check my Ph during the day or in the evening as at that point I can see what the high level in my tank is. I also make sure that my Alk & Cal are in line and actually don't even check my Ph that often.

 

[SlamaJama]

hey galley,
i dose the 2 part as well, seems like a big swing in ph, maybe dosing the needed amount in smaller increments, and making sure that u use equal amounts of parts 1&2 may have avoided that swing. u want to chk ur alk/cal/Mg all at the same time of the day so that u can notice how much of the Cal in particular, is beeing used up over a 24 hr period...use this i got from spykes its an awesome tool.

http://home.comcast.net/~jdieck1/chem_calc3.html

BTW, u can come over anytime to c if i have anything u like to frag for u...lmk