Magnesium deficiency is a very common problem in aquaponics, its symptoms closely resemble potassium deficiency. Magnesium is very important for the growth, production, and health of your aquaponics plants. Magnesium deficiency can cause serious problems for your plants, it can make plants more susceptible to common diseases and problems with pests.
How to Identify Magnesium Deficiency – Symptoms to look out for include:
- Loss of older growth – Magnesium deficiency affects older leaves first.
- Chlorosis – Interveinal chlorosis or yellowing of the leaf tissue between veins.
- Burning along the fringes of the leaves
- Occasional cupping
- Older leaves begin to discolor – Older leaves and those lower on the plant may begin yellowing or develop a reddish-brown tint.
- Necrosis – New leaves may develop brown spots of necrosis where the tissues did not develop properly.
- Low pH levels – The pH level of the system can be an indicator of magnesium deficiency.
How to Treat Magnesium Deficiency
It is important to resolve the magnesium deficiency quickly, before it does serious damage to your plants. It is necessary to know that the plants problem may not have anything to do with the amount of magnesium in the water in the system. Treating magnesium deficiency will depend on your pH level, as a low pH can affect the plants ability to uptake the available magnesium. It also important to balance the nutrients potassium and calcium. An imbalance in these nutrients will make it difficult for plants to absorb the other.
Method 1 (If the pH levels are low): If the pH level in the system are low, mix 1 part
potassium hydroxide and 1 part hydrated or agriculture lime. This will raise, potassium, calcium, and magnesium concentrations. This will also raise the pH levels.
Method 2 (Neutral pH levels): Add weekly dose of soluble kelp concentrate powder, as well as a mixture of chelated calcium and magnesium sulfate. This will help
balance the nutrients in the system.
Method 3 : If the problems are severe enough that achieving balanced pH and
nutrients will likely not going to be enough to restore plants health. Then it is
recommended to supplement magnesium with Epsom salt.
Adding Epsom salt to aquaponics:
• Use approximately one ounce for every 1,000 gallons
• Add Epsom salt directly into the fish tank
• Continue to add Epsom salt on a regular schedule until deficiencies improve.
Method 4 : If there is a severe deficiency, mix one tablespoon Epsom salt with one-gallon water and spray directly onto plant leaves.
How to Prevent Magnesium Deficiency
Ensure that calcium and potassium are balanced in the system as these can affect magnesium uptake. It is important to to monitor th pH regularly, as low pH can make it harder for your plants to uptake available magnesium. Maintaining pH levels is the key to preventing future magnesium deficiancy issues. It is also recommended to keep some Epsom salt on hand, and adding it to the system as needed.
