Is your calcium reactor, DIY dosing pump, or drip system clogging frequently or dripping at an inconsistent rate? I recommend upgrading with two Flow Control Pinch Valves (Item Code: FT0002).
One pinch valve is good, Two pinch valves are better! With micro-ball valves or just one pinch valve, you are choking the output line too much allowing sediment to build eventually clogging the effluent line. 
Two pinch valves solves this issue by reducing the flow rate at two points and allowing the effluent to flow freely through larger choke points.
Add one Flow Control Pinch Valve at the output of the reactor or pump. Dial this valve down to reduce the output tubing to a trickle flow.
Add a second Flow Control Pinch Valve at the end of the output tubing and adjust to the desired drip rate.