Some things done to improve calcium reactor reliability :
1) Added a sponge to the top to prevent loose media from being sucked into the recirculating pump. I've been hit by damaged impellers despite following instructions of keeping a safe recommended media fill height to the inlet pipe.
Suspect that media can get small/light enough as it melts and gets lifted by the strong flow.
2) Improve reliability of effluent flow
Some adjust to a high effluent flow rate to minimize the chance of clogging. However, i also means the system needs a lot of CO2 to maintain the low pH. Personally, I try to keep it to a fast drip & reduce CO2.
Some reefers who prefer a slower flow dip the tube under water to minimize exposure to air (one of the main reasons for causing the tube to clog). But the issue is that its hard to check flow rate
So I combined both ideas & seem to be quite reliable. With this, i'm able to monitor the drip rate, lower CO2 bubble count & have the tube under water. Currently running around 40ml/min