Root Tab Plants
Heavy root feeders thrive on root tabs: Amazon swords, crypts, aponogetons, and vallisneria. Their large root systems extract nutrients from substrate.
One tab per plant every 3-4 months. Push deep into substrate near roots, not surface.
Liquid Fert Plants
Water-column feeders: mosses, anubias, java fern, and most stem plants. They absorb nutrients through leaves.
Use balanced all-in-one liquid ferts (Tropica Specialised, Seachem Flourish) once weekly.
Combined Approach
Most low-tech tanks have a mix of plants. Use root tabs for swords/crypts + liquid weekly for general plant mass.
Reduce dose if algae appears — low-tech tanks need less fert than high-tech.
Timing and Observation
Add liquid after water changes for best absorption. Watch new leaves for yellowing (iron deficiency) or stunted growth (overall deficiency).
Withhold ferts if tank is algae-heavy — let plants starve out competition first.