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Nutrient Deficiency in Aquaponics Systems

Tomatoes are such a wonderful indicator as to what nutrient may be missing in your Aquaponics system.
Now, here is an interesting one to look at.

Blossom End Rot

Blossom End Rot, a classic deficiency of calcium.

Take a close look at the tomatoes in the photo. You will see that the ends of the fruit are deformed and rotting. This condition is actually called ‘Blossom End Rot” and that is because the “rot” is on the blossom end of the newly forming fruit.

This is a classic case of “Calcium” deficiency.

You may see the same problem on Capsicum or Peppers because they are the same family of fruiting plants and they may suffer the same problem in the same way.

Blossom End Rot

So, how do we get Calcium into the plant to head off this problem?

When we are making adjustments to pH in our Aquaponics system we most often use Calcium Carbonate to do that and the happy coincidence is that we are adjusting pH upwards and also adding Calcium to the system at the same time.

You may say “I have done that and sometimes it makes no difference”

The Calcium may not assimilate well if there is a shortfall of Potassium in the system.
Potassium helps the calcium to move around in the plant.

Calcium can also have difficulty being taken up by the plant when water and air temperatures are low.

It is very difficult to isolate just one element an a system as the only problem. 
In excellent soil, as one will find on a rain forest floor, plant nutrients are all in that soil and are taken up by the plants as and when they are needed. The plants know what they need, they do not need to be trained. If the nutrients are in a natural state, that is, not synthetic factory-style nutrients, the plants will take up what they need and ignore the rest.

Some will tell you to buy this element or nutrient, and some of this or that and add them but I prefer to adopt what I call “the shotgun approach”.

We need to find an all-encompassing nutrient supplement that is organic in nature and apply that to the system providing a wide spectrum of natural nutrients for the plants.

The ideal nutrient supplement is a good quality seaweed extract or kelp.

We have found over the years that the application of seaweed extract weekly to our systems, large or small will produce excellent, robust plants that do not exhibit nutrient deficiencies. The addition of a quality seaweed or kelp extract will not harm the fish.

There is much more to discuss and we will add more info in the next newsletter.
We cover this subject matter in fine detail in our Aquaponics Master Class and our Aquaponics Design Course

Posted By Practical Aquaponics on 24th February 2020

Updated : 24th February 2020 | Words : 449 | Views : 63779

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Nutrient Deficiency in Aquaponics Systems

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