I will include a dosing pump I used with the stirrer.
It's a medical grade peristaltic pump capable of running 24/7.
I have two of these and about 10' of Tygon tubing to go with it (lifetime supply). I used to replace the tubing every 6 months.
For the $300 you can have both pumps and the stirrer.
I used to fill the stirrer daily directly from my RO/DI using two solenoids and controlled my Apex. I have a replacement lid for the stirrer with a float switch to shut off the fill valves about 3/4 of the way up.
The pump is controllable with the included relay box. I had Apex to turn it on/off based on the salinity and sump level.
This setup was flawlessly topping my tank with kalk for last 5 years.
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Denis
150g SPS reef;3x250WHQI,Tunze Streams,Wavebox,Neptune Apex,fishroom in basement
,reefing since 93,SPS since 99.
TOTM June 2010