You are running the flow rate so slow that your reactor is in effect becoming an anerobic zone. Which is breaking down ammonia etc. Same thing that happens in a DSB.
What size tank do you have? 25 drips per min is not a lot when you look at the volume of a tank.
I am running a 33 gallon tank and have an effluent rate of 75 milliliters per minute.
I highly doubt that with those rates you are getting much if any use out of your reactor. It is becoming a denitirifcation device. or partially so. Not a Ca reactor.
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Darren
Always strive for the optimum environment, not the minimum environment
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