A Beginner’s Guide to Hydroponics

Switching from organic to hydroponic

There can be several reasons why a grower may choose to make the jump to hydroponics. Some of them may be the need to carry bags of soil around, ending up with a dirty grow room with small yields, having to throw away large amounts of soil at the end of every harvest and the need to buy new soil each time. 

For those who are ready for a system that offers a plug in and play mentality, hydroponics serves the ultimate purpose and is commonly used in commercial vegetable and fruit farming. Compared to soil grown, hydroponics may be more costly in terms of nutrients, however the return on investment is significantly greater than traditionally soil grown methods. 

The benefits associated with growing Cannabis using hydroponic methods

1. Plants fed with hydroponic nutrients will grow bigger and faster during 18/6.
2. There is no need to hand water the plants and only to fill a reservoir.
3. The final yields can be twice or three times the size compared to organics.
4. Hydroponics is a clean and sterile way to grow Cannabis indoors with no mess.
5. There are various systems available to use, depending on the grower’s skill level.
6. For small growing spaces, hydroponic systems will return the highest yields.
7. Due to the fast rate of growth, short vegetative times of 7–10 days are needed.

The different hydroponic systems explained

The beauty of organic farming is that everyone has their own methods of producing what they believe is the most superior crop possible. However, when it comes to hydro, there are a number of different systems available, which all have their own unique style.

Aeroponics 

An aeroponic system works by misting the roots of a Cannabis plant with a nutrient solution. As the roots hang inside a chamber, they are sprayed with a fine mist, allowing them to access nutrients and oxygen. Plants can grow very quickly and produce large yields. 

Skill level: Aquaponics are best suited for an experienced grower who is familiar with low pressure and high pressure aeroponic. Also, those with experience with deep water culture are ideal for these fast-paced systems.

Aquaponics 

Using Koi fish, a specific food and ultimately a fish tank environment, plants will float on the water, with their roots permanently submerged. As the fish create food waste, the plants absorb the nutrients, allowing them access to high amounts of dissolved oxygen and organic feed. 

Skill level: Indoor growers will never grow using aquaponics, and you will usually find these types of systems being used for rooftop farming, or the more extreme cultivator who has the luxury of a Koi carp pond and is fond of growing Cannabis. 

Deep water culture (DWC)

DWC systems operate using an air pump, which creates high amounts of dissolved oxygen inside the reservoir where the plant’s roots are permanently set. As plants are able to uptake nutrients constantly, they have the ability to become very large when grown in these systems and are often associated with the most productive systems you can invest in, 

Skill level: Things can go wrong quite quickly when growing Cannabis using DWC, so it is important to have a thorough understanding of pH, E.C and water temperature management. 

Reverse deep water culture (RDWC)

A complex system that houses together a number of deep water culture buckets. By connecting several buckets together at once and using one pump to feed each individual system at the same time, a grower can save time on reservoir changes and is able to yield massive plants when done right. 

Skill level: We recommend RDWC for the well versed grower who has several DWC grows under their belt, and is more than comfortable controlling pH, E.C and can afford to do large reservoir changes and add high volumes of nutrients. 

Top dripper systems

Probably the easiest system to set up, and also the perfect for a first time grower making the shift from organic to hydroponic. Top dripper systems basically use drip lines and a drip stake, and a pump to supply nutrients for 15 minute intervals. How often the plants are fed each day will depend on the size of the plants, which stage of the life cycle they are at, and the light intensity. 

Skill level: We recommend using dripper systems, and working with a substrate such as coco, or hydroton. Pumps can be left on for 24 hours a day when using hydroton meaning it is not possible for a grower to over water their plants. 

Nutrient film technique (NFT)

A great example of these systems are the ones used for growing lettuce in drain pipe style fixtures. As the roots of the plants sit on a bed, a fine film of nutrients passes by, allowing them to have access 24 hours a day to nutrient solution. Some modified versions more popular for growing Cannabis plants are the long black plastic tables that sit the plants on a 30 degree slope, with the nutrient solution recirculating back.

Skill level: NFT systems are really simple and easy to use, and will reward a first time grower with excellent results and big buds. The pump will be left on 24 hours a day, so there is not much need for maintenance, apart from reservoir changes every 3–5 days.

Flood and drain 

A system that allows for nutrient solution to flood a table, housing plants. As the nutrients are pumped on the table and allowed to drain after a moment, the roots are able to uptake nutrients and intake oxygen. The most common way to grow using flood and drain is to use hydroton and grow in a sea of green set up using a high number of smaller sized plants. 

Skill level: Another easy to set up and use system ideal for small growing spaces. You do not really see many growers these days using flood and drain, however when done correctly, then can produce great yields indoors. 

What does pH and E.C mean, and why are they necessary?

Potential hydrogen or pH refers to how acidic or alkaline your water nutrient solution or water source will be. When growing Cannabis using hydroponic nutrients, you should aim for a pH level of 5.5-6.5. 

The best way to check your pH is to use a digital pen. The easiest way to adjust the pH level of your water or nutrient solution is to use pH up or down and add whichever is needed accordingly. 

Mistakes to avoid when using hydroponic systems

1. The water temperature of your nutrient solution in the reservoir should be around 18-20 degrees Celsius. Check the temperature to see if you are consistently hitting this mark, as cold temperatures can cause nutrients to lock out, become cloudy and for plants to lose vigor. 
2. Only investing in one air pump or water pump is not wise, and you should always have a back-up pimp, in the event of an emergency. Avoid being left stranded without a pump if one fails after long term use, and invest in plenty of spares if you can afford. 
3. During the vegetative stage, plants grown in hydroponic systems can become very large and bushy. We recommend switching your timers to 12/12 after 7–14 days, depending on how much space you have. Avoid growing for more than 2 weeks to prevent overcrowding once flowering begins. 
4. It is very important to change the reservoir and keep it fresh, clean and filled with nutrients. A reservoir can be changed every 3–5 days, depending on how mature the plants are, so avoid allowing your nutrient solution to sit for more than 5 days at a time before changing to a fresh batch.

Conclusion

There are many rewards for those who are ready to take on the challenge of indoor hydroponics. There is no need to worry about carrying 50 liter bags of soil and compost around, constantly sweeping up dirt, and no more small yields. We advise taking the time to learn about hydroponics before investing in your first systems, to avoid being overwhelmed and to allow you to produce some record-breaking harvests!