Hydroponics - Diseases

Root Rot

This problem is widespread, especially with cheap systems from the Internet and with beginners. Root rot usually has to do with insufficient oxygenation or an incorrect pH value.

Other causes:

Incorrectly placed air stones or insufficient compressor performance in DWC systems (except Kratky).
Insufficient water movement and oxygenation in the system (except Kratky).
The plants cannot develop aerial roots if they are planted incorrectly.
The water temperature is too high (Maximum temperature should be below 28°C).
The PH value is outside the guideline value of PH 5.5-6.5
Algae growth from exposure to light draws oxygen from the system.
Roots were not adequately cleaned prior to transfer to the system.

Common Remedies:

Clean the entire system and refill it.
Clean the roots well under running water.
System temperature during operation should be kept below 28°C.
PH value regulated between 5.5 - 6.5 and the EC value according to the specifications.
Light entering the nutrient solution must be blocked to counteract the growth of algae.
With a 3% hydrogen peroxide admixture with 6ml/L root rot can also be minimized and prevented.

Micro and macro nutrient deficiencies

The most common deficiencies in hydroponic systems are magnesium, manganese, phosphorus, nitrogen, potassium, iron and calcium deficiencies.

Magnesium deficiency:

Magnesium is one of the most common deficiency problems in hydroponic systems. This can be remedied simply by adding Epson salt.

Mangan deficiency:

Manganese and iron are closely linked. If the iron content is too high, the absorption of manganese can be reduced. Manganese is an important trace element. It ensures strong cell walls, metabolism, the structure of the chloroplasts and photosynthesis. It inhibits photosynthesis which also slows growth. A disturbed root system, an iron content that is too high or a pH value that is too high can be the causes here.

Phosphorus deficiency:

Characteristic reddish to purple leaf discoloration on older leaves, especially in leaf veins. The growth of the plant and the development of roots is severely limited. The remedy is to adapt the nutrient solution with a higher phosphorus content.

4-18-38 Tomato Masterblend has already proven itself worldwide on a wide range of plant types.

Nitrogen deficiency:

Root rot and/or an incorrect PH value favor a nitrogen deficiency.
Too low a temperature of the nutrient solution can also be decisive here.
Pale yellow leaves are a clear sign of this.
A readjustment of the nutrient solution can help here.

Potassium deficiency:

With a lack of potassium, evaporation is reduced. The result is that the temperature in the leaves rises and the cells burn. This happens primarily at the leaf edges, where evaporation is usually highest. Flowering is reduced and leafy areas die off.

Potassium can also be added to the system....

Iron deficiency:

Manganese and iron are closely linked. (see manganese deficiency)
A PH value above 6.5 can lead to iron deficiency.
Iron is supplied via the NPK nutrients in the form of micronutrients.

In alternative DIY scenes, iron screws are often simply added to the tank to increase the iron content.

Calcium deficiency:

A very common problem which is very easy to solve.
Calcium deficiency usually manifests itself as localized putrefaction of tissues and consequent stunted growth.
CalMag or calcium nitrate is commercially available and is a quick fix.
Alternatively, you can boil eggshells, shred them and dissolve them with strong vinegar.

Caterpillar Infestation

Affected leaves and visible caterpillars must be removed. Caterpillars should never be killed as they usually form beautiful butterflies.

Alternative spraying agents:

* Water - neem oil - biological dish soap or dissolved curd soap.
* Chop the garlic and chillies, let stand for an hour mixed with water, drain and mix with the spray water at a ratio of 1:10.

Garlic water, even mixed with raw onions, is a natural repellent. Even if the garden smells like a kebab shop for a while, the plants will thank you.

Other alternatives:

Leaves can be dusted with tobacco ash, algae lime or garlic powder.

Snails on visit

Snails are always annoying and a permanent work site.
Hydroponic systems are usually less accessible. Due to the design of these systems, however, electrical barriers are perfect (self-adhesive metal strips which are supplied with a 9V battery or low-voltage power pack).
Two or more strips are glued to the tank or pipe with a small distance and supplied with a voltage. Voltages of 9V are absolutely harmless to humans and pets.

Aphids

Arguably one of the worst invaders.
Aphids slowly kill the plants and are protected by ants. Here it is usually necessary to act quickly. The ants can be reduced with fly bands, but the lice usually only have a few natural enemies in hydroponic systems.
Washing off with a strong jet of water is a first choice, but this can sometimes cause damage to the plants.
A mixture of soft soap/potassium soap with water (15ml/1L) is a good option for a weak infestation.

Alternative spraying agents:

* Water - neem oil (alternatively rapeseed oil) - biological detergent or dissolved curd soap.

* Chop the garlic and onion, mix with water and allow to steep for an hour, strain and mix with the spray water at a ratio of 1:10.

Fungal Infestation

Mold infestation in plants is usually promoted by incorrect watering, too little air movement due to a lack of trimming or poor choice of space, and too high humidity.

Alcohol, hydrogen peroxide or vinegar are suitable home remedies for removing mold. Alcohol should be at least 70% concentration. Medicinal alcohol or methylated spirits are well suited. The hydrogen peroxide bleach should be bought in at least a 3% solution. A mixing ratio of 1:3 with water spray is recommended and should be repeated every 2-3 days.

For mixtures with alcohol or vinegar, adding ~35-50ml/L would be a good choice.

Spider Mites

Spider mites or spider mites are easily recognizable by their fine webs. Here it is important to act quickly.
They bite into plant leaves and suck out the succulent plant fluids. In addition to the obvious damage it does to your plant, it also makes it more susceptible to disease.

In addition to the usual household sprays (see aphids)

The following mixtures can be used here:

Vinegar based:

Mix 1/8 cup apple cider vinegar (white vinegar works too) with 1 cup water, 1/2 tsp baking soda, and a few drops of mild dish soap in a spray bottle.

Alcohol based:

Mixture of 1 cup rubbing alcohol and 4 cups water and then spray the solution onto your plants. Cover the stems, flowers and leaves thoroughly. Alcohol kills spider mites by dehydrating them.

Mosquito Larvae

Sometimes small pests can also be found in the tank and reservoir. This is often favored by a too high PH value.
The nutrient solution should usually be changed every 2-3 weeks or refreshed via a circulation system. A filter in front of the pump can remove quite a bit of floating pests.
If multiple systems are used, an elevated buffer tank with circulation and filter stages is generally beneficial.
Addition of hydrogen peroxide (3-9%) not only supports root growth, prevents mold growth, it is also helpful against amphibious larvae and insects.