Dutchfest FAQ's
Use the line that matches the medium. Hydro Grow and Bloom A&B are for recirculating and run-to-waste hydroponic systems on inert media. Coco A&B is written for coco coir, which binds calcium and magnesium and lets nutrients go differently. Running the hydro formula in coco is the usual reason a crop shows a calcium shortfall mid-cycle.
They are the two stages of one hydroponic base. Grow carries more nitrogen for leaf and stem; Bloom puts the weight on phosphorus and potassium for flowers. Change from Grow to Bloom when the plant changes stage — they are not meant to run together.
At the start of the run: through propagation, transplant and the first weeks of vegetative growth, while the plant is still building roots. Adding a root product late does little, because the root mass is largely already there. The bottle is 1L, which lasts a long way at typical dose rates.
It is the flowering additive. Run it through the second half of the cycle on top of Hydro Bloom or the Coco base — it does not replace either. Stick to the label rate rather than assuming a heavier dose is better. Additives lift total feed strength, and too much EC in flower creates more trouble than it is worth.
Hydro Grow and Bloom bases are in 1L, 5L and 20L. Coco A&B is in 1L and 5L. Both additives are 1L only. That span covers a home tent through to a commercial room on the hydro side. Buy what you will actually use in a season — concentrates do not get better as they sit.