When ph is rising?

So what is dropping to make the ph go up? Is it calcium, or mag?

 

Dissolved CO2. That's why when someone is having pH issues, we tell them to make sure the surface of their water is rippling with a powerhead....it helps gas exchange.

Hydrogen is a gas. As a result, the pH (or Power of Hydrogen) is affected most by other dissolved gasses....namely Oxygen and Carbon Dioxide.

 

I am rippling away there is excellent water movement on the top of the water? any other thoughts?

 

If you're getting good water movement, then when your lights turn on, your pH will start rising. The various algaes in your tank (including the symbiotic algae in our corals and other inverts) will start taking up CO2 and produce Oxygen with it. With good surface exchange, this Oxygen will also cause the CO2 to offgas which allows the pH to also rise. (BTW, this is also the reason some people run a refugium and they light the algaes in their fuge opposite the lighting schedule of their display tank....it keeps the high and low pH for the day more stable).

 

rising alk will bring up pH too

 

Well this is interesting to me. I have a fuge I have a large sump, The pariamiters are all good I just did not check the calcium or mag as I left my kits at a friends a week ago. I did not dose or do a water change in a while but my ph is rising? I have the lights on the refugium on the off hrs of the DT. I literally have done nothing different so in baffled? I am doing a 50 gallon water change tonight to drop my nitrates a little so I will see if anything changes.

 

when you say rising, to what values are you talking about?

 

For 2 years its been stuck at 8.1 now its rising to just over 8.4 and swinging to 8.3 its not dangers high its actually in the area but the fact that this happened in a few days after not ever getting up to 8.4 unless I dose makes me wonder why the difference.

 

I wouldnt worry about it. 8.3 is ideal. Ive seen my ph run 8.0-8.4.. just make sure your dkh is 9-12. do you run AC all year or leave windows open more lately?

 

Dissolved CO2 makes pH go down, not up... if you're opening windows, it could be that the CO2 is escaping in exchange for oxygen.