persistently low pH

[durango_doug]

I have had water in my 90 gallon for two weeks now, and have been recording my parameters and actions in excel. I attached the file. I thought my initial low pH was strange because I have been dosing kalk. I placed the air pumps for the skimmer outside to push out some of the CO2, and this seemed to have helped as the pH came up to around 8.2 for a few days. however, all day today it has been back down around 8.0. I don't have lights on the tank yet. Please help me understand what is going on here.

I should also mention that I am using a calibrated pinpoint pH meter, and have confirmed its measurements with a salifert kit. also, notice that I moved my pH probe on Thursday to get better readings.

Thanks,

Doug

[durango_doug]

i guess the file was too big. i took off the graphs, so it should work now.

[Randy Holmes-Farley]

Once you start lighting the tank, the pH should rise considerably as photosynthesis consumes CO2. So I wouldn't worry about it yet.

I tried to download the file, but even after 10 minutes on broadband, it hasn't come through. ???