Seachem Plant Pack: Enhancer (NPK)
Water type
Freshwater
Seachem Plant Pack: Enhancer (NPK)
The three macro nutrients a planted tank runs short of first — dosed independently, not locked into one ratio. Seachem Plant Pack Enhancer (NPK) bundles 100 mL bottles of Flourish Nitrogen, Flourish Phosphorus and Flourish Potassium, so you can add exactly the macro nutrient your plants are short of, guided by test results rather than a fixed blend.
It suits medium to high-light planted aquariums where light is no longer the limiting factor and macro nutrients are — the stage most planted tanks reach once the easy wins from Plant Pack Fundamentals are already in place.
What's in the pack
- Flourish Nitrogen (100 mL) — nitrate plus a complexed ammonium form plants prefer; no free ammonia reaches the water, since it only becomes available as plants take it up.
- Flourish Phosphorus (100 mL) — a nitrate-free potassium phosphate solution (0.3% available P₂O₅), so you can lift phosphorus without pushing nitrate up alongside it.
- Flourish Potassium (100 mL) — a concentrated potassium supplement, the macro nutrient most easily depleted in a fast-growing planted tank.
Why dose N, P and K separately
A combined NPK product locks you into whatever ratio the bottle was mixed at — fine until one nutrient runs low while another is already at target. Dosing from three bottles means you add what a test kit or the plants themselves show is missing, rather than force-feeding a nutrient that's already sufficient.
Dosage and directions
| Bottle | Beginner dose | Raises |
|---|---|---|
| Flourish Nitrogen | 2.5 mL per 160 L, twice weekly or as needed | Nitrogen, roughly equivalent to 1 mg/L nitrate per full dose across the tank |
| Flourish Phosphorus | 2.5 mL per 80 L, once or twice weekly or as needed | Phosphorus by about 0.05 mg/L (0.15 mg/L phosphate) per dose |
| Flourish Potassium | 5 mL (1 capful) per 125 L, 2–3 times weekly or as needed | Potassium by about 2 mg/L per dose |
Dose in response to deficiency signs — stunted growth or chlorosis for nitrogen, dark green but stalled growth for phosphorus, yellowing or pinholed older leaves for potassium — rather than on a fixed schedule regardless of what the plants are showing.
Which bottle runs out first?
All three bottles are 100 mL, but they don't last the same length of time, because each is dosed at a different rate. At the beginner dose above: Flourish Potassium is the first to empty, at around 2,500 L of dosed tank water; Flourish Phosphorus follows at around 3,200 L; Flourish Nitrogen lasts longest, to around 6,400 L. In practice that means you'll likely need a second bottle of Potassium before the other two run out — worth knowing before you assume the pack empties evenly.
Suitable for, and not suitable for
- Suitable for: medium to high-light freshwater planted aquariums where macro nutrients, not light, are limiting growth. Safe around shrimp and other freshwater invertebrates at labelled doses.
- Not suitable for: reef or marine tanks. Not a substitute for testing — dosing phosphorus or nitrogen beyond what plants can use will feed algae, not plants.
Safety
Overdosing phosphorus or nitrogen beyond plant uptake capacity is the main risk with any macro-nutrient dosing — it feeds algae rather than plants. Monitor with a nitrate and phosphate test kit and dose to the reading, not just the calendar.
Goes well with
- Seachem Plant Pack Fundamentals — the trace element, iron and liquid carbon side of a complete dosing regime.
- A nitrate and phosphate test kit — to dose to an actual reading rather than a guess.
- Individual Flourish Nitrogen, Phosphorus or Potassium bottles — for topping up whichever nutrient in this pack you burn through first.
Warranty and delivery
Covered by Seachem's standard quality guarantee in addition to your rights under Australian Consumer Law. Standard shipping; no cold chain or special handling required.
Common questions
Do I need all three bottles at once?
Only dose the nutrient your plants or test results show is low. Having all three on hand just means you're not caught short when a deficiency shows up.
Will this cause an algae bloom?
Only if you dose past what your plants can use — test before and after dosing so nitrogen and phosphorus are being taken up, not accumulating.
What's the difference between this and Seachem Flourish (the all-in-one)?
Flourish is a broad-spectrum trace element supplement and deliberately low in nitrogen and phosphorus. This pack covers the three macro nutrients Flourish doesn't, dosed independently.
Is it reef safe?
No — this pack is formulated for freshwater planted aquariums, not marine or reef systems.
Which bottle should I expect to reorder first?
Flourish Potassium, at the standard dosing rates above — it's the first of the three to run out on a typical dosing schedule.
