Korallin Calcium reactor help?

[sphelps]

I wouldn't run a Ca reactor without pH control but seems your problem is related to either your regulator, needle valve or maybe a check valve?. What pressure is the tank at compared to the regulated pressure? Is it constant? I would also consider trying a new needle valve and check valve if you're using one. To test the check valve you could run it without one and see if you get constant bubble flow. I does sound a little like a blockage somewhere in the CO2 line so be sure to check anything else that could cause restriction.