[TheJohnner]

So I have the CO2 pumping out of the cylinder via a milwaukee regulator and SMS122 ph controler, but I set the controller for a ph of 6.5 and often it reads 6.7 or 6.8 and it doesn't always release CO2 bubbles at those readings.....why not? It would seem that it should in order to lower the ph back down to 6.5. Any thoughts on this??

- John

 

[jjlin78]

their might be a problem with the solenoid.

 

[theredben]

What is the differential for that controller. If you set it to 6.5, does it turn on at 6.6, 6.7,6.8? Does it turn off at 6.5,6.4,6.3? If the differential was set to .2pH, it would turn on at 6.7 and turn off at 6.3, if the diff was .1 it would turn on at 6.6 and turn off at 6.4. I have no experience with this controller so I cannot say how it works, but maybe it is on a timed operation like if the pH is higher than 6.6 for 30sec, 1min, etc... then it turns on. Just throwing out ideas.

Edit: just did some searching. Looks like the differential is .05pH (not sure how it can be that accurate). Here is a link to a good explanation:

http://www.plantedtank.net/forums/equipment/5966-milwaukee-sms122-setpoint-question-again.html

 

[TheJohnner]

Thanks,
This sounds like it could be the problem. I will have to look into this when I get home.