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growing weed with aquaponics

Growing weed with aquaponics

Luckily there are natural sources to get extra nutrient supplementation without seriously affecting your fish. For example Maxicrop is a common nutrient additive made out of seaweed that works well in an aquaponics system to add potassium and trace minerals without hurting your fish.

It may be possible to simply supplement your tank with extra nutrients during the flowering stage, but it can be harmful to fish to add an excessive amount of extra nutrients unless the plants use most of it up before the water is re-circulated back to the rearing tank! Extra planning and water testing may be needed to manage which nutrients are currently available.

Aquaponics may be the most efficient way there is to cultivate both fish and plants at the same time because combining them together reduces the cost of farming each one individually! In big commercial operations, aquaponics is used to produce profitable combinations like tilapia fish and lettuce. In smaller setups, aquaponics is a sustainable, low-technology and efficient way to create food even with infertile land and low resources – aquaponics dramatically reduces the amount of water needed for raising fish, while producing high-nutrient plants at the same time!

Although fish are the most common species used for aquaponics, other aquatic creatures like shrimp, crayfish or prawns can also be used. Both edible fish and ornamental fish can be used successfully in an aquaponic system. Generally you want to pick a species that is hardy and can tolerate crowding. Tilapia is an edible fish that adapt very well to aquaponics, and koi or goldfish are great choices for ornamental fish since they are nice to look at and can thrive in sub-optimal environments.

Aquaponics is the art of combining aquaculture (growing fish in tanks) with hydroponics (growing plants in water). It’s sort of like organic hydroponics!


Aquaponics is spectacular at producing fish and plants at the same time. If a cannabis grower would like a constant supply of fish to eat or sell, an aquaponic system simply can’t be beat!

Some growers will introduce a worm farm (vermicompost) to the system to supplement nutrients naturally while breaking down the solid waste from fish which can’t be processed by bacteria. This is one way to actually “complete” the cycle inside the system.

The Secret to Success with Marijuana & Aquaponics is Patience

Growing weed with aquaponics

Once you know the amount of water the soil layer can hold, you can water this layer separately with phosphate and potassium rich organic fertilizer without fear that it will contaminate the fish water. Too much phosphate and potassium is unhealthy for the fish and microbes, but is necessary for flourishing plant growth.

Once your system is fully cycled, you can now put your fish and plants into your grow. It’s useful to continue to monitor your system until you’re sure a good balance is reached between the plants, bacteria and fish.

You can purchase a turn-key aquaponics system kit or build one from scratch. To properly grow cannabis, we are going to set up our system to function by flood and drain. To do that, your water pump will need to function on a timer.

First, drill two holes in the grow bed that will fit two bulkheads, one for the fill and one for the drain. Next, place your fill and drain into the bulkheads and connect the pump. Plug the pump into the timer and set it on for 15 minutes and off for 45 minutes. This is a far more frequent flood cycle than in hydroponics but remember the water needs to be regularly filtered for the fishes’ sake.

The Build

Hello, growers! Consider this your bare bones guide to understanding and building a simple Aquaponics system. There is much more to cover than this brief overview, but it should help you better understand how cannabis grows in Aquaponics. Using this technique, we’ve been able to grow some great, high-yielding plants. The one pictured above we grew using Aquaponics and measures almost nine feet across.

Next you will cycle your system before adding fish. Cycling is the process of establishing a colony of bacteria that can carry out the nitrogen cycle in your system. The bacteria start with the ammonia in fish waste in covert it step-wise into nitrate fertilizer, which can get taken up by the plants once you put them in.

In a dual root zone you separate a layer of traditional expanded clay media with a layer of burlap, or other root permeable material, and add a soil layer on top. This dual root zone allows you to house your terrestrial microbes in an upper soil layer, which can be amended however you’d like, and aquatic layer to house your aquatic microbes. This allows you to have some longer-term nutrient retention in the upper root zone while allowing great gas exchange and water to your plants at the same time. It also enables you to gain the benefits of both biomes of microbes and maximize natural nutrient input going into your plants.

The Dual Root Zone

With Aquaponics we have five knobs we can turn to adjust our available nutrients. You can supplement using fish safe additives directly into your sump tank or fish tank. You can supplement by changing the diet of your fish, or the frequency or amount of feeding, to increase output of desired nutrients. You can add soil amendments of your choice to the soil you use for your upper half of the root zone pot. You can use any liquid supplement you desire in the upper root zone at any time during growing. And lastly, you can foliar spray if you also choose. This gives you a wide range of options when you want to supplement your plants. We have done a lot of work towards figuring out what works best in each application. You can learn all about it over at We have everything from classes and education into so-called turn-key systems.

It is important to cycle your system before planting. Without cycling you will not have enough beneficial bacteria to provide your plants with the nutrients they need. To tell if your system is cycled you need to test your nitrogen levels starting with ammonia. You want to use pure ammonia, or an AquaCycle fish-less cycling kit, and bring your ammonia to 4 ppm. Anything much above a 4 ppm will start to kill bacteria, but start with at least 2 ppm.