Utah Aquaponics

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How To Grow Marijuana In An Aquaponic System

By on 04/17/2017

Growing marijuana is rather a contentious subject these days. However, if you’ve consulted with your lawyer/consultants and you know for a fact that it’s absolutely legal in your state or have legal permission, then you may want to know how to grow marijuana in an aquaponic system. If you don’t maybe learning how to print t-shirts will be better. (We are not liable for any illegal use of this information).

Here are some tips that you should keep in mind:

  1. You need a lot of patience. An aquaponics system is a constant juggling act involving fish, bacteria that converts the fish waste into useful nutrients, and plants. So you’ll need time to at least colonize the bacteria, and then more time afterwards to get the balance right.

It takes a while to get that proper balance. This may involve changing the water, adding or removing fish, managing pH, and adding nutrients.

  1. Take note of the high nutrient needs of the marijuana. Building your bacteria biofilter can take at least 6 months, so in the first few months your marijuana may not get the nutrients it needs from the fish waste. This means that during the first few months of your system you’ll need to supplement the nutrients.

Also, during the flowering-budding stage, the cannabis plants can really consume a lot of nutrients. So you will need to account for this. It helps if you already have experience with tomatoes for aquaponics, as they both have similar nutrient needs. They’re very different from the simpler needs of herbs and lettuce (which are best for beginners). 

  1. You may need to maintain 2 different tanks. That’s because the nutrient needs will be different for the vegetative cannabis and the flowering cannabis. With 2 tanks, you can better optimize your aquaponics setup.

It is possible to just add more nutrients for your tank during your cannabis flowering stage. But there’s a risk to this. Having too much nutrients that your cannabis plants can’t use before the water is circulated back to the fish tank may be harmful for the fish.

  1. Test the water constantly to find the nutrients you need to supplement. During the flowering stage, you probably will need to supplement with additional iron, calcium, and potassium. Even more phosphorus may be needed too.

5. Use safe nutrient additives. If you want to put in more potassium and other trace minerals, you can put in Maxicrop. It’s a popular additive made from seaweed, and it’s common for aquaponics.

You can also try potassium carbonate and calcium hydroxide. These can provide potassium and calcium, while they also raise the pH. For an aquaponics system that not yet properly established, low pH is a common issue.

  1. You may even want to try putting in a worm farm. It’s a method called vermicomposting, and the worms can break down waste which the bacteria can’t process.

Again, you will need patience, experience, and a bit of luck on your side if you want to learn how to grow marijuana in an aquaponic system. Just make sure it’s legal—we aren’t advocating that you break the law!

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