Nutrient Mixing Sheet
Your feed chart sets the rates. This sheet scales them, converts the units, and keeps the batch repeatable.
BFCBrilliance · bfcbrilliance.com/tools/hydroponic-nutrient-calculator
The arithmetic and the units
- Dose for a reservoir
- volume x rate x strength
- 1 US gallon
- 3.785411784 litres
- ml/L → ml/gal
- multiply by 3.785
- ml/gal → ml/L
- divide by 3.785
- ⚠ Mixing those units
- is a factor of nearly 4
- ⛔ NEVER mix concentrates
- add each to the FULL water separately
- ⚠ Target EC / ppm
- from YOUR manufacturer's feed chart
- pH
- adjust AFTER the nutrients are in
This mix
- Date
- Crop and stage
- Product
- Reservoir volume
- Strength %
- Part A rate
- Part B rate
- Part C rate
- PART A ml
- PART B ml
- PART C ml
- EC after mixing
- pH after adjusting
Reservoir log
| Date | Volume | Strength | EC | pH | Notes |
|---|---|---|---|---|---|
Mixing a reservoir
- Rates taken from THIS product's feed chart for THIS stage
- Label units checked - ml/gal or ml/L
- Water volume measured, not judged by the tank's rated size
- Each part added to the FULL volume of water separately
- Stirred fully between parts - never concentrate into concentrate
- Doses measured with a syringe or cylinder, not splashed
- Strength reduced deliberately for seedlings if that is your practice
- EC checked after mixing
- pH adjusted LAST, after everything is dissolved
- Readings written down so a problem can be traced
Never concentrate into concentrate
Calcium in one part and sulphates or phosphates in another form compounds that drop out of solution the instant they meet undiluted. You get a precipitate in the bottom of the tank and a feed missing the nutrients you paid for, with nothing to warn you but a little cloudiness. Each part goes into the full volume of water on its own, stirred in before the next.
A meter turns top-ups from a guess into a reading
Plants take up water and nutrient at different rates, so reservoirs drift - up if you always top up with full feed, down if you always use plain water, and which happens depends on crop, stage and conditions. An EC meter is inexpensive and is the single most useful instrument in a hydroponic setup, because it tells you which way yours is actually going.