so today for the first time since setting up My tank I have people over. Windows where closed and AC turned on. My ph went into a free fall from around 8.1 to 7.7. How acceptable is this swing ? I cannot run a o2 line outside and I was looking into co2 scrubbers but the media could get expensive. Eventually I will have a cheto reactor online to help with ph but not sure what to do about this.