Aquatic plants

Plant organisms that live completely or partially submerged. They absorb nitrates and phosphates, produce oxygen and provide shelter for fish.

Detailed explanation

Aquatic plants are the best natural filter there is. They absorb nitrates, phosphates, ammonium and CO2, returning oxygen. A densely planted aquarium has much more stable water parameters than an unplanted aquarium.

The plants are divided according to light and CO2 needs. Easy plants (Anubias, Microsorum, Cryptocoryne, Vallisneria, Echinodorus) grow with moderate lighting and without additional CO2. Fussy plants (Rotala, Ludwigia, Hemianthus, Glossostigma, Riccardia) require bright light, injected CO2 and thorough fertilisation.

Fertilisation is divided into macro and micro. Macronutrients (nitrogen, phosphorus, potassium) often come from fish metabolism. The microelements (iron, manganese, boron, zinc) must be integrated with liquid fertilisers. Iron is often the limiting factor.

CO2 is the most important nutrient for plants. Without additional CO2 growth is limited. With a pressurized CO2 system (cylinder, reducer, diffuser) the difference is impressive. We aim for 20-30 mg/l of dissolved CO2.

Regular pruning stimulates compact, bushy growth. Stem plants are cut and the tops replanted. Rosette plants are thinned by removing old leaves.

In the marine aquarium, aquatic plants are not used (except macroalgae in the refugium). In their place, corals play a similar role thanks to symbiotic zooxanthellae.

In ponds, aquatic plants are fundamental for balance: water lilies, water irises, rushes and floating plants such as Pistia and Salvinia.

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