Macronutrients are the minerals plants need in the largest quantities. Besides fuelling growth, each of them influences how well a plant can defend itself against disease. The effects are not always straightforward: the right amount strengthens the plant, while too much or too little can make it more vulnerable.
Nitrogen
Nitrogen is the classic example of a double-edged nutrient. A shortage weakens the plant and slows its defence responses. Too much, however, produces soft, fast-growing tissue with thin cell walls that pathogens find easy to invade. The aim is a steady, moderate supply that matches the plant’s growth rate; LGND Nitrogen allows precise dosing.
Phosphorus
Phosphorus is central to energy transfer and is needed for the plant to build defensive compounds. Adequate phosphate supports strong roots and faster recovery from damage. Keep it in balance with nitrogen; LGND Phosphat makes this easy.
Potassium
Potassium is one of the nutrients most consistently linked to disease resistance. It strengthens cell walls, regulates water balance and reduces the build-up of sugars and amino acids in leaves, which would otherwise feed pathogens. Since aquarium waste contains almost no potassium, supplementing with LGND Potassium is essential in planted tanks.
Calcium
Calcium binds the cell wall together and stabilises membranes. Plants with enough calcium form tougher tissue that resists the enzymes many pathogens use to break through. Calcium also acts as a signal inside the cell, helping to switch on defence reactions.
Sulphur
Sulphur is needed for certain amino acids and for a range of sulphur-containing compounds that help plants resist fungi and bacteria. Deficiency is rare in aquariums, as tap water and most fertilisers contain sulphates.
Magnesium
Magnesium is at the centre of the chlorophyll molecule and activates many enzymes. A well-supplied plant photosynthesises efficiently and has the energy to maintain its defences. In soft or RO water, magnesium and calcium should be restored with a remineraliser such as LGND Evenness.
In practice: healthy plants come from balanced nutrition, not from pushing one nutrient. For an easy, balanced base, an all-in-one fertiliser such as LGND Avalon supplies macro and micronutrients together.