I posted this in the neptune forum but though I post it here to see if I can get an answer sooner. if anybody knows that would be great. I'm using fusion to setup my CO2 configuration to control my cal-rx. I have it set at High Value: 7.20 and Low Value: 7.10 and On When "high". The outlet doesn't turn off when my pH is reading under 7.20, in fact its reading 6.74 and it's still on. It's set to auto and using the whatever fusion is offering to program.