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Super-absorbent polymer spheres/chunks with 50/50 and Bovedas for two-way "trimming".
Works excellently, and you never do anything to maintain the Bovedas, they self-maintain. All you do is refill the containers of the polymer spheres/chunks with distilled water or occasionally fresh 50/50.
Oh, and Western/Oasis Caliber IV units, very carefully and accurately calibrated.
No HF beads. Not paying some guy $65 (or whatever it is) for a certain kind of sand he probably got for 10 cents as part of a giant bulk order from his sooper seekrit supplier. I have my own retirement to worry about, I ain't gonna fund his!
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