Grow-Genius Mono-Silicic Acid is a 40% w/w monosilicic acid concentrate that gives plants silicon in the form they take up directly. It's dosed by the drop, not the capful. At 0.3 ml per 10 L, this 100 ml bottle makes about 3,333 L of feed. That's roughly a year of weekly reservoir changes for a home grower. Quick Bloom Lights stocks it in Sydney, direct from Grow-Genius UK.
How concentrated it is
Most silica additives dose in whole millilitres per litre. Grow-Genius doses at 0.3 ml per 10 L. Here's what one 100 ml bottle makes at each rate:
| Use | Rate | 100 ml bottle makes |
|---|---|---|
| Root feed, standard | 0.03 ml / L | ~3,333 L |
| Root feed, upper rate | 0.05 ml / L | 2,000 L |
| Foliar spray | 0.5 ml / L | 200 L |
When to use it
Grow-Genius direct that it goes in at the roots from seed germination or cutting propagation right through to a few weeks before harvest, weekly at minimum and up to every feed. Foliar spraying is weekly to fortnightly and stops at early flowering on species with dense or compact flowers.
How to dilute it
Add it to your reservoir or watering can after your other nutrients and additives, stir, then check pH and EC as normal. No pH adjustment is required for the silica itself.
Root feed: hydro, coco, soil
| Water / nutrient solution | Standard (0.03 ml/L) | Upper (0.05 ml/L) |
|---|---|---|
| 1 L | 0.03 ml (about 1 drop) | 0.05 ml |
| 10 L | 0.3 ml | 0.5 ml |
| 20 L | 0.6 ml | 1.0 ml |
| 50 L | 1.5 ml | 2.5 ml |
| 100 L | 3.0 ml | 5.0 ml |
| 200 L | 6.0 ml | 10.0 ml |
Foliar spray
| Sprayer volume | 0.5 ml/L | Woody stems, max 0.75 ml/L |
|---|---|---|
| 1 L | 0.5 ml | 0.75 ml |
| 2 L | 1.0 ml | 1.5 ml |
| 5 L | 2.5 ml | 3.75 ml |
Spray weekly to fortnightly at lights-off or in low light, covering the tops and undersides of leaves. Stop foliar sprays at early flowering on species with dense or compact flowers.
What silicon does for your plants
Plants lay silicon down in their cell walls, and most base nutrients supply little or none of it. Published plant science links a good silicon supply to stronger stems and leaves, better tolerance of heat and water stress, and a tougher leaf surface that forms part of the plant's own defences. Because this is already monosilicic acid, the plant doesn't have to wait for the silicon to break down into a form it can use. And because it's pH neutral, it won't push your pH up the way potassium silicate does.
Grow-Genius states it's compatible with mycorrhizae and bacteria-friendly growing techniques at the recommended rates, and readily biodegradable at 95% over 28 days (OECD Test Guideline 301F).
Specifications
| Brand | Grow-Genius (UK) |
| Active | >40% w/w monosilicic acid, 21% Si |
| Volume | 100 ml |
| Root feed rate | 0.03–0.05 ml per litre |
| Root feed frequency | Weekly to every feed |
| Foliar rate | 0.5 ml per litre (max 0.75 ml/L, woody stems) |
| Use from / until | Germination or propagation, to a few weeks before harvest |
| Makes | ~3,333 L root feed, or 200 L foliar spray |
| pH | Neutral, no adjustment required |
| Mixing order | Add after other nutrients |
| Suits | Hydro, coco, rockwool, soil |
| Transport class | UN1993, Class 3 flammable liquid, PG III |
| Safety Data Sheet | Download SDS (PDF) |
FAQ
Another 40% mono-silicic acid is cheaper. What's the difference?
Check the dose on the label before you compare bottle prices. Divide the bottle price by the litres of feed it actually makes at its own recommended rate — this one makes about 3,333 L per 100 ml. That's the number worth comparing.
How long will 100 ml last me?
At 0.3 ml per 10 L, a 50 L reservoir changed weekly uses 1.5 ml a week, so 100 ml lasts over a year. A single tent hand-watered with 10 L a week would take years to use it.
Does it go in first, like other silica?
No. Potassium silicate goes in first because it's alkaline. Grow-Genius directs that this product goes in after your other nutrients. Follow the instructions for the product you're using.
Can I run it every feed?
Yes. Grow-Genius rate the root feed from weekly up to daily, so every feed is within the recommendation.
Will it upset my pH?
No. It's pH neutral, so it won't move a balanced reservoir. Check pH after all nutrients are in, as you normally would.