Often times pH drops when there is an excess of C02 in the tank, as well as the
air in the room that tank is in. When I open my doors and windows and fill the
house with fresh air, my pH rises quite a bit. However, in Texas it is either
super hot or quite cold, so I only get to do this maybe 2 months a year.

Try aiming a powerhead or two at the surface of the water to cause rippling,
which promotes gas exchange. This is more involved, but if your protein skimmer
is a venturi driven one, you could run a longer piece of airline tubing from the
pump all the way outside, to suck in fresh air all the time.

Marc


livingrock wrote:

In between water changes the further away I go from the previous WC,
my PH drops off the scale, if I add a buffer it raises it a bit but by
the next day its down again, all of the rest ofm my parms look ok.
Does anyone know what causes low PH?

Thanks.

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