- Sku: 466
- Vendor: Seachem
Seachem Flourish Potassium
Seachem Flourish Potassium is a concentrated potassium source for the planted aquarium, supplying 50,000 mg/L of potassium. Potassium is one of the three key macro nutrients (nitrogen, phosphorus, potassium, or NPK) and is vital to vigorous growth. It can become depleted in a fast-growing tank or when source water is low in minerals, making it the limiting factor to growth. Browse our full range of additives and supplements and the rest of the Seachem lineup.
Why Seachem Flourish Potassium
How to Use
Shake well before use. Add 5 mL (one capful) to every 125 liters (about 30 US gallons) twice a week, or dose as needed in response to signs of potassium deficiency. Heavily planted or fast-growing tanks may need more. For best results, use as part of a complete fertilizer routine.
Choose Your Size
| Size | Best for |
|---|---|
| 50 mL | Nano and small planted tanks, or trying Flourish Potassium |
| 100 mL | Standard small to mid planted aquariums |
| 250 mL | Mid-size and well-planted tanks |
| 500 mL | Large or heavily planted tanks |
| 2 L | Multiple tanks or frequent dosers, best value per mL |
Specifications
| Brand | Seachem |
|---|---|
| Type | Liquid potassium (K) supplement |
| Concentration | 50,000 mg/L potassium |
| Best for | Planted aquariums and soft or RO water (freshwater) |
| Dose | 5 mL per 125 L (30 gal) twice weekly |
| Sizes | 50 mL, 100 mL, 250 mL, 500 mL, 2 L |
Recommended Pairings
- Use with Flourish Nitrogen and Phosphorus for a full NPK routine, found in our Seachem range
- Browse all additives and supplements
- Shop everything for planted aquariums
Frequently Asked Questions
How do I know my plants need potassium?
A common sign is yellowing or small pinholes in older leaves, since plants move potassium to new growth first. Fast-growing tanks deplete it quickly.
When is potassium the limiting factor?
In heavily planted tanks and those using soft or RO water, potassium is often used up faster than nitrogen or phosphorus, which slows overall growth.
How does it differ from Nitrogen and Phosphorus?
Each targets one macro nutrient. Use Nitrogen, Phosphorus, and Potassium together to dose the full NPK your plants need.
Is it safe for fish and shrimp?
Yes, when dosed as directed it is safe for fish and invertebrates in the planted freshwater aquarium.
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Seachem Flourish Potassium
