How much DE?
Exactly how much diatomaceous earth your batch needs. No more guessing, no more clogged plates.
In the app, on the Boil stageTime of season
Method
How to do it
Straight mix (easiest, best under 25 gal)
Bring your syrup to filtering temperature (180 to 190°F). Stir the full DE amount directly into the hot syrup until no dry clumps remain. Pump through the press; recirculate the first quart or two back into the batch until the output runs bright and clear. The cloudy first pass is just the filter cake forming. Then run to your finishing tank. Stop when the pressure gauge reaches 40 PSI: the plates are full.
Precharge method (cleaner first pour, best over 25 gal)
Heat a few gallons of water, stir the precharge DE into it, and pump the DE-water through the press to coat the plates. Drain the water without disturbing the cake. Now run your hot syrup through. It hits a ready-made filter bed, so the first pour comes out clear. Keep a light ongoing dose in the syrup for long runs, and re-charge whenever pressure hits 40 PSI.
If something goes wrong
Pressure spikes immediately: too much niter for the cake. Add more DE to the batch, or switch to the late-season rate. Syrup stays cloudy: the cake hasn't formed yet; keep recirculating, and check that plate papers are seated. Press "fills" after a gallon or two: late-season niter load. Use 0.75 cups/gal and consider precharging even for small batches. Flow slows to a trickle below 40 PSI: the syrup has cooled. Filtering below ~180°F thickens syrup and blinds the cake fast.
Rates scaled from the Smoky Lake filter-press baseline (3.25 cups per 7" plate, area-proportional for larger plates); food-grade DE only.
The full walkthrough lives in SweetRun.
Step-by-step press instructions, density check, finishing temps, canning guide and grade reference, plus your whole season’s logs and economics. Offline, no account, and your data stays yours.
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