Atami and Bloom
Atami’s US range on the left, Bloom on the right, matched on the job each bottle does. Atami is heavy on stage boosters and PK. Bloom brings the organic tonics that aren’t on their US list.
Last checked 5 November 2026 · Public information only
This Fit Report is a summary of publicly available information about Atami and its products, taken from their own website, labels and published material as of 5 November 2026. We’ve linked each source so you can check it yourself. Rates are as printed on each company’s own pages; we don’t show prices. It isn’t affiliated with, endorsed by or approved by Atami, and product names belong to their owners. Products, rates and claims change, so please confirm current details with the manufacturer before making any decision. Spotted something out of date? Email nathan@bloomyellowbottles.com and we’ll correct it.
Stage boosters on both sides, tonics on one.
Atami’s US range is mostly boosters you dose daily at the stage they’re for: root, growth, pre-bloom, bloom and finish, plus PK, silicon and a coco substrate. Their US product list has no seaweed, fish, humic, carbohydrate or cal-mag bottle. That’s where Bloom’s weekly tonics sit, alongside the Atami boosters a grower already runs.
- Stays as is: B’cuzz Coco Substrate and Blossom Builder Tabzz.
- Both have one: root, veg, flip, finish, PK and silicon. Plan the stack, or test them side by side.
- Not on their US list: kelp, tuna, humic acid, carbohydrates, cal-mag, sea minerals and foliar sprays.
Where each bottle sits in the cycle
Atami’s timing in grey, Bloom’s in yellow, across shared stages of the grow.
| Stage | Root | Veg | Flip | 3–4 | 5+ | Last 2 | Flush |
|---|---|---|---|---|---|---|---|
| Atami, per their pages | |||||||
| B’cuzz Root (first 2 weeks) | |||||||
| Rootbastic (first 3 weeks) | |||||||
| B’cuzz Growth | |||||||
| Silicbastic | |||||||
| B’cuzz Bloom (Atami) | |||||||
| B’cuzz PK 13-14 (Atami) | |||||||
| Bloombastic | |||||||
| Rokzbastic | |||||||
| Blossom Builder Tabzz | |||||||
| Bloom, per Bloom’s weekly feed charts | |||||||
| Roots | |||||||
| Pre | |||||||
| Ultra | |||||||
| Phat (weeks 3 and 4) | |||||||
| Ooze (wk 5 to flush) | |||||||
| Final (with Ooze) | |||||||
| Seafuel | |||||||
| Seaweed · Humate · Sea Minerals | |||||||
| SWTNR | |||||||
| Cal-Mag | |||||||
| Groigen (foliar, as needed) | |||||||
| Florigen (foliar, as needed) | |||||||
| PK (as needed) | |||||||
| Silica | |||||||
Timing comes from each Atami US product page. Their pages give phases (growth, flowering, last 4 to 6 weeks, last 2 to 4 weeks) rather than numbered weeks, so we’ve placed them on these stages (our read). Their PK 13-14 page says to flush with water in the last week. Bloom’s bars follow its weekly feed charts; pale Bloom bars are as-needed bottles.
Why each one fits
What the Bloom product does, the research behind that kind of input, and where it sits in a program that already runs.
Kelp and tuna in the tank
What it does. Seaweed is southern bull kelp at 1 ml/L weekly, seedling through flush. Seafuel is tuna and kelp at 1 ml/L weekly, clone through late flower, tapering at the flush.
Reviews of seaweed extracts report effects on growth and stress tolerance across many crops. Work on protein hydrolysates, which fish inputs belong to, links them to nutrient uptake, mostly under stress. None of it tests these bottles or cannabis.
Ali et al. (2021), Plants (review) · Malécange et al. (2023), Int J Mol Sci (review)
How it stacks. Add once a week on top of the daily Atami doses. Our read: dose the weekly bottles on the same day each week so runoff readings stay easy to follow.
Humic acid and trace minerals
What it does. Humate is 10% humic acid at 2.5 ml/L weekly, seedling through flush. Sea Minerals is trace minerals from sea water at 0.13 ml/L weekly, veg to bloom.
A major review links humic substances to changes in root structure and function tied to nutrient uptake, including more lateral roots. It doesn’t test either company’s products.
How it stacks. B’cuzz Root already lists humic acid for the first two weeks. Humate carries on from there through the flush (our read).
Carbohydrates and cal-mag
What it does. SWTNR is carbohydrates and potassium at 1 ml/L weekly, veg week 2 to the flush. Cal-Mag is calcium and magnesium with iron and zinc, labelled 6.8-0-0, at 1 ml/L weekly through grow and bloom, stopping at the final flush.
How it stacks. Atami’s grow guides lean on coco, where growers often add cal-mag (our read). Cal-Mag goes in with the base; SWTNR goes in after it. These are feed tools, so there’s no study cited for them here.
Foliar sprays for veg and the flip
What it does. Groigen and Florigen are sprayed at 20 ml/L, lights off, every few days as needed. Groigen from seedling through veg; Florigen from the stretch to early bloom, stopping once buds set.
How it stacks. They go on the leaves, so they sit outside the daily Atami tank doses altogether (our read).
Their line, Bloom’s fit at a glance
Matched on job, not NPK. Atami prints oz per US gallon with ml per litre beside it, dosed daily when watering. Bloom prints ml per litre on a weekly feed chart. Tap a tag to filter.
Keep the coco. Bloom’s liquids go in the water that runs through it.
A tablet format Bloom doesn’t make. Our read: count it in your late-flower PK if you also run PK.
All three are early root bottles. B’cuzz Root lists amino and humic acids; Roots is amino acids, B vitamins and fulvic acid.
Both are veg-stage additives. Atami’s runs daily from the growth phase; Pre sits in mid veg.
Both go in around the flip. Plan which one carries the stretch, or test them.
Both are PK. Atami’s runs through flower; Bloom’s is an as-needed bottle at peak bloom. Plan the stack, or pick one.
More PK in the Atami line. Their Bloombastic page warns against adding another PK product.
Both are finishing bottles. Rokzbastic is a mineral PK; Ooze is plant extracts, fulvic acid, vitamins and amino acids.
Both are silicon. Bloom’s is potassium silicate, labelled 0-0-4. Pick one.
Southern bull kelp, and a tuna and kelp tonic, through the cycle.
10% humic acid, plus trace minerals from sea water.
Carbohydrates and potassium from veg week 2, and calcium and magnesium for soil, coco and hydro.
Foliar sprays for veg and the flip, outside the feed line.
Put it side by side
Where both ranges have a product for the same job, the fair answer is a test in your own room. Here’s what to watch and how to keep it fair.
Keeping it fair
- Same plants. Clones off the same mother, same cultivar, same age.
- Same room. Same light, climate, media, pot size and watering.
- Same base. Keep the base feed and EC the same on both sides.
- One change. Change only the product being tested, and write down what you see each week.
Where the programs complement each other
Atami boosters, Bloom tonics alongside
Their US list has no seaweed, fish, humic, carbohydrate or cal-mag bottle. Seaweed, Seafuel, Humate, SWTNR and Cal-Mag go in weekly at 1–2.5 ml/L alongside the daily Atami doses.
One PK plan, not three
Atami’s PK 13-14, Bloombastic, Blossom Builder and Tabzz plus Bloom’s PK all carry P and K. Bloombastic’s own page warns about stacking PK, so a grower picks one PK plan and runs the rest around it (our read).
Foliars outside the tank
Groigen and Florigen go on the leaves at 20 ml/L as needed, so they don’t touch the Atami daily dosing at all.
Already covered
- Root and veg. B’cuzz Root, Rootbastic and B’cuzz Growth.
- Flip and bloom. B’cuzz Bloom, Bloombastic and Blossom Builder Liquid.
- PK and finish. PK 13-14, Rokzbastic and Blossom Builder Tabzz.
- Silicon and media. Silicbastic and B’cuzz Coco Substrate.
Stays exactly as is
- B’cuzz Coco Substrate. Bloom has no growing media.
- Blossom Builder Tabzz. Bloom has no tablets or dry products.
- Your base feed. Atami’s US list doesn’t carry a base; keep the one you run.
- Atami boosters that are working. Keep them, or test Bloom’s next to them.
Background, science and sources
Who Atami are
Atami calls itself a premium plant nutrition and substrate brand, founded in 1997. It runs regional sites for more than ten countries, including a US site. The pages we read don’t state a head office, owner or US distributor.
Atami’s brands are B’cuzz, Bastics, ATA, ATA NRG, VGN, Atami Substrates and Wilma Grow Systems. The US site carries B’cuzz Root, Growth, Bloom, Blossom Builder Liquid, Blossom Builder Tabzz and PK 13-14, the Bastics line (Rootbastic, Bloombastic, Rokzbastic, Silicbastic) and B’cuzz Coco Substrate, with grow guides for soil, coco and hydro.
What each company brings
Atami: Stage boosters for root, growth, pre-bloom, bloom and finish, three PK products and PK tablets, a liquid silicon, a coco substrate, and grow guides for soil, coco and hydro.
Bloom: one additive for each stage of the crop, seaweed, humic and sea mineral inputs, foliar sprays, and weekly feed charts for soil, coco and hydro. Rates and timing are on every product page.
Cropping Solutions, the other brand under Agricultural Organics, isn’t part of this report.
Dose basis: how each side counts
Atami prints oz per US gallon with ml per litre alongside, and most of its US pages say to add the product daily when watering. Bloom prints ml per litre of nutrient solution, on a weekly feed chart.
So B’cuzz Root at 0.5–1 ml/L daily and Roots at 0.5 ml/L weekly aren’t the same weekly amount, even where the number matches. The analyses differ too.
Mix calculator
Rates as printed on each company’s page (1 US gallon is 3.785 L). Bloom’s rates are per litre of nutrient solution, dosed weekly per its feed charts. Pick a product and your tank size.
Silicon in the plantWell supported
Luyckx and colleagues (2017) review silicon in plants: how it builds up in cell walls, and its links to tolerance of drought, salt, metals and pathogens.
Why it matters here: Silicbastic and Bloom’s Silica are both silicon products. The review is general plant science and doesn’t compare products.
Potassium in the plantWell supported
Hasanuzzaman and colleagues (2018) review potassium’s roles: enzyme activation, photosynthesis and tolerance to drought, salt and heat.
Why it matters here: most of Atami’s flower range and Bloom’s PK carry potassium, so it’s the shared ground. The review doesn’t compare products or timing.
Sources, all viewed 5 November 2026
Atami: Home · US site · B’cuzz · Bastics · B’cuzz Root · B’cuzz Growth · B’cuzz Bloom · B’cuzz PK 13-14 · Blossom Builder Liquid · Blossom Builder Tabzz · Rootbastic · Bloombastic · Rokzbastic · Silicbastic · B’cuzz Coco Substrate · Bastics and B’cuzz soil guide (PDF)
Bloom: Roots · Pre · Ultra · Phat · Ooze · Final · Seafuel · Seaweed · SWTNR · Humate · Cal-Mag · Groigen · Florigen · Sea Minerals · PK · Euro · Grow · Flower · Silica · OrganiShield
Last checked 5 November 2026. Public information only. Not affiliated with, endorsed by or approved by Atami; product names belong to their owners. Please confirm current details with the manufacturer. Corrections: nathan@bloomyellowbottles.com. All Fit Reports