Cake: pH, EC, Concentrate and DWC

Mix Cake at 3 g per gallon of water (0.79 g per liter), by itself, and pH it to 6.2. There's no EC target for Cake. For a doser, dissolve 384 g of Cake in a half gallon of water, top up to 1 gallon and dose it at 30 mL per gallon (1:128).

Cake alone means no Veg or Bloom A+B, no calcium and no Cal-Mag. Cake helps block nitrogen uptake so the plant finishes. For when it starts (week 8 of an 8-week cycle, the final 2 weeks for autos and Granular grows), see When to Start Cake and How to Make the Transition.

pH and EC

pH the finished Cake feed to 6.2. Don't mix to an EC number. Cake isn't supposed to match your Bloom EC, and what you read also depends on your water. Weigh 3 g per gallon and leave it there.

Getting it dissolved

Cake takes longer to dissolve than the other powders, especially in cold water. Clear water doesn't mean it's done; check the bottom of the tank too.

• Add the powder to the water while mixing. Too little water, or water poured onto the powder, can leave a hard mass on the bottom.
• Give it a thorough mix. We've used 90 °F water and a drill mixer for stock.
• Brush settled powder off the bottom while the pump runs.
• pH can move while Cake is still dissolving. Keep it circulating, then measure and adjust the finished feed.
• Keep undissolved chunks out of your drippers.

Cake concentrate

1. Start with a half gallon of water.
2. Add 384 g of Cake while mixing.
3. Keep mixing as you top up to exactly 1 gallon.
4. Dose at 30 mL per gallon of feed (1:128), by itself.

Scale the same way for bigger tanks: 384 g per gallon of finished stock. If you add extra water, the stock is weaker and 30 mL per gallon no longer gives you 3 g. Keep the Cake stock to itself: no A or B, no microbes. RunClean can go in the Cake stock if your feed needs pH down.

If Cake pH crashes

A Cake reservoir shouldn't drop in pH, and a fall isn't a sign the plants are eating. If you see one, check the probe against fresh calibration solution before you add anything. Then send us the mix, the starting and current EC and pH, and anything you or a controller added.

AutoPots and bottom-fed systems

Go straight to Cake in the reservoir. Skip the plain-water flush you'd do in top-fed pots, and skip the plain-water interval between Cake reservoirs. Granular AutoPots work the same way: Cake at 3 g per gallon in the reservoir water, not top-dressed into the medium. Keep pH 6.2 in the base.

DWC

Run Cake at 3 g per gallon and pH 6.2 through harvest. There's no plain-water finish after Cake. Keep the root-zone aeration running.