Hydroponic Additives
Hydroponic additives that layer over any base nutrient range — root inoculants, silica, bloom boosters and resin enhancers from Green Planet, Plant Mechanics and more, stocked in Australia and shipped fast.
Hydroponic Additives That Earn Their Place in the Reservoir
Bloom Boosters & Resin Enhancers Growers Reorder
Massive Bloom Formulation and Rezin by Green Planet are among our most reordered products for a reason — measurable flower size, aroma and resin gains when run through the flowering stage. If you only add one thing to your bloom feed, start here.
Root Stimulants & Silica for Stronger Plants
Root Builder's beneficial bacteria build the root zone early, and Super Si by Plant Mechanics toughens cell walls for thicker stems and better stress tolerance. Both slot into any feed schedule, hydro or coco.
Hydroponic Additives Matched to Your Base Range
With 149 additives on the shelf, the hard part is choosing — not finding. We run these products ourselves, so ask us what actually stacks with your base nutrients and we'll tell you straight, backed by 14 years of growing.
Build the rest of your feed: hydroponic nutrients, coco nutrients, DWC & recirculating nutrients and foliar sprays.
FAQs
Do I need additives if I'm already using a base nutrient?
No. A quality base nutrient covers essential feeding on its own — additives are optional upgrades targeting specific outcomes like root mass, flower size or resin production once your fundamentals are dialled in.
Can I mix additives from different brands?
Yes, in most cases. Root inoculants, silica and bloom boosters generally stack fine with any base range — add silica to the reservoir first, and introduce one new additive at a time so you can see what's working.
When should I add a bloom booster?
Bloom boosters go in once plants shift into flower, typically from week two or three of the flowering stage. Follow the product's feed chart for dose and duration.
Welcome to The Grow Guys
We built The Grow Guys from the soil up — well, coco and perlite. Before we sold gear, we bought it, ran it, and learned the hard way what's worth the money and what ends up in the shed. That's the filter everything on our shelves passes through. No sales scripts, no rebadged junk, no telling you what you want to hear. Just gear we'd run ourselves and advice from people who actually grow. Chasing higher yields, tighter flowers, or your first harvest? You're in the right place.
FAQs
Calculated at checkout by weight and destination. Free shipping over $499*.
Order by 2pm and it ships the same business day from Invermay, Tasmania.
500+ products across 40+ brands, every one filtered through 14 years of real growing experience. Shipping Australia-wide.
30-day change-of-mind returns on unopened, unused products. A 10% restocking fee applies and return shipping is at your cost.
Call, email, or walk into the Invermay shop. You'll get a grower on the other end, not a script.