The Athena Pro Line Bloom is the dry flowering base of Athena's Pro Line. Paired with Pro Line Core, it replaces Pro Line Grow at the switch to flower and carries the crop through to the finish, supplying the phosphorus, potassium, magnesium and sulfur that flowering plants draw on hardest. It's a fully soluble powder you dissolve into a stock concentrate, built for rooms where cost per litre of feed matters.
Built for the flowering stage
Flowering plants need more phosphorus and potassium to build flower mass and support their higher metabolic load. Pro Line Bloom delivers both at 0-12-24, alongside 3% magnesium and 9% sulfur — sulfur being the element plants use in producing aroma and flavour compounds. There's no nitrogen in Bloom itself; that comes from Pro Line Core, which is why the two are always used together.
Two parts, measured by weight
The Pro Line recipe is simple: for every 1 gram of Pro Line Bloom, use 0.6 grams of Pro Line Core. Dissolve each into its own stock concentrate — Athena recommends 2 lb per US gallon (about 240 g per litre), and never more than 2.5 lb per gallon (about 300 g per litre) — then inject or dose both to your target EC. Always measure by weight, not volume, and never combine the two as dry powders or concentrates.
The Pro Line runs on constant EC: once flower starts you hold one feed strength and let the Bloom-to-Core ratio do the work, rather than changing the recipe every week.
Full specifications
| Manufacturer | Athena (Los Angeles, USA) |
| Line | Pro Line — constant EC |
| Type | Dry, fully soluble fertiliser |
| Guaranteed analysis | 0-12-24 · 3% Mg · 9% S · 0.1% chelated Fe |
| Ingredients | Potassium phosphate, potassium sulfate, magnesium sulfate, iron DTPA |
| Stage | Flowering — replaces Pro Line Grow at the flip |
| Mix ratio | 1 g Pro Line Bloom : 0.6 g Pro Line Core (by weight) |
| Stock concentrate | 2 lb per US gal (≈240 g/L) recommended; 2.5 lb per US gal (≈300 g/L) maximum |
| Dosing guides | Pro Line dosage guidelines (PDF) · Pro Line liquid mix chart (PDF) |
| Sizes | 4.53 kg (10 lb) box with 5 inner pouches · 11.34 kg (25 lb) box |
| Compatibility | Stock tanks and all dosing systems, including Dosatron and Netafim |
FAQ
Can I use Pro Line Bloom on its own?
No. It contains no nitrogen and no calcium — both come from Pro Line Core. Bloom and Core together make the complete flowering recipe.
Do I switch to Fade at the end?
Yes. For the final 3 weeks of flower, Athena's procedure replaces Core with Pro Line Fade and keeps Bloom running, cutting nitrogen out as the crop ripens.
Which size should I buy?
The 4.53 kg box comes as 5 inner pouches, handy for mixing consistent concentrate batches. The 11.34 kg box suits larger rooms going through Bloom quickly. Through flower you use Bloom at a higher rate than Core (1 : 0.6), though Core also runs through veg.
Can I use it in DWC?
Athena publishes no DWC procedure for the Pro Line — its DWC and RDWC guidance is written for the Blended Line. For deep water culture, use Athena Blended Bloom A & B instead.
Can I mix it with the Blended Line?
No. Blended and Pro are separate systems with separate feed charts. Pick one and stay with it.
