Fertilizer Myths: Aquarium Products and Hydrogen Peroxide Don't Help Houseplants

Owner uses Seachem Flourish, Kent Marine (aquarium fertilizers), and hydrogen peroxide in water.

Expert Assessment

Aquarium fertilizers formulated for submerged plants – not terrestrial houseplants.
Hydrogen peroxide: no proven benefit for plants.
Nutrient deficiencies rarely cause houseplant problems.

Light and water drive 95% of plant health. Fertilizer is oversold.

Cheapest balanced fertilizer at 1/4 label strength – harmless, minimal benefit.

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