-50% on a selection of fish food
In aquaponics, the fish supply the nitrogen, but the water is often short of iron, potassium and sometimes magnesium or calcium. These supplements make up for those shortfalls without harming the fish or the bacteria. Potassium bicarbonate raises pH and KH while supplying potassium, potassium sulphate feeds flowering and fruiting, and Epsom salt corrects a lack of magnesium.
Before adding a supplement, test the water: drop tests for iron, potassium and magnesium show what is really missing. The article Which fertiliser to use in aquaponics? details the useful additions.
Frequently asked questions
Related articles
Advanced aquaponist
What to sow in autumn in aquaponics
Autumn is not the end of the growing season — it is the start of the most peaceful one. Here is what to sow, when to do it and how to achieve leaf harvests through to the depths of winter
Read the article
Advanced aquaponist
Growing pots for aquaponics
The net pot is an unassuming but decisive accessory in aquaponics: it supports the plant, houses the grow medium and allows water and oxygen to circulate freely. This guide explains how to choose the right model according to diameter, mesh,
Read the article
Advanced aquaponist
Vermiponics: worms in aquaponics
Vermiponics involves introducing compost worms into the grow medium beds of an aquaponic system, where they break down fish sludge and plant debris that bacteria then convert into assimilable nutrients. This page covers suitable species, introduction densities, the conditions that
Read the article
Beginner aquaponist
Growing tomatoes in aquaponics
Hungry for nutrients and a lover of warmth, the tomato finds aquaponics an ideal growing environment. This comprehensive guide takes you from choosing a variety through to harvest, covering pH, hand pollination, and pruning, to produce flavoursome fruit throughout the
Read the article