Seachem Flourish Comprehensive Plant Supplement

Seachem Flourish is a comprehensive plant supplement for the natural freshwater aquarium. It provides micro elements, trace elements and other nutrients, including calcium, magnesium and iron. It does not contain significant levels of nitrogen or phosphorus. This page covers the 100 mL / 3.4 fl. oz. bottle, the 500 ml bottle and the 2 L / 67.6 fl. oz. bottle.

Dosing

Seachem’s direction is 1 capful (5 mL) for each 250 L (60 US gallons), once or twice a week. For smaller tanks, each cap thread is about 1 mL, which makes small doses easy to measure.

What it covers and what it does not

Flourish supplies the broad range of trace nutrients plants need in small amounts. Because it has little nitrogen or phosphorus, it relies on fish waste and food for those. In a lightly stocked tank with many fast plants, you may need a separate nitrogen and phosphorus source.

Storage

Seachem recommends refrigeration 3 months after opening. The liquid’s color varies by batch, depending on the temperature at blending; that does not affect how it works.

Choosing a size

• 100 mL: a small tank, or a trial before committing
• 500 ml: a typical home planted tank
• 2 L: large tanks or several tanks; keep in mind the refrigeration advice once opened

Where it fits

Flourish is the water-column side of a planted routine. Pair it with root tabs like Seachem Flourish Tabs for heavy root feeders. For a simpler iron and potassium product, see API LEAF ZONE.

Reading your plants

Pale new growth often points to iron or trace shortages, which Flourish addresses. Yellowing old leaves and stalled growth across the tank may point to nitrogen instead, which Flourish does not supply in meaningful amounts.

Algae balance

Dose to the label, keep lighting moderate and keep plant mass high. Healthy, dense plants outcompete algae for the same nutrients.