Geo Reef CalcRx - recalibrate after CO2 tank change?

[NYCMAN]

I just changed the CO2 tank on my GEO Reef reactor for the first time last night. The CO2 pressure halved from its max, so I tested Alk. Dropped from 8.8 to 7.0. Alarming! So changed the tank. Today it measured 6.5. More alarming! Do I need to completely retune the reactor when changing CO2 tanks? Seems the CO2 tank and pressure are another parameter in the mix (along with affluent rate and PH in reactor). Is this the case?

 

[SPR1968]

I can’t answer the specific question, but I can bump the thread to see if we can get you some help