Frequently Asked Questions

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Hydroponic Basics FAQ
Lighting FAQ
Insect and Fungus FAQ
Water And Nutrients FAQ
Hydroponic Basics FAQ
1. What is hydroponics?

hy•dro•pon•ics Noun: The process of growing plants in sand, gravel, or liquid (or other mediums), with added nutrients but without soil. Hydro is Latin for water and Ponos means works or labor. Water works! The main principles of hydroponics are increased oxygen to the root zone and liquid feed delivered directly to roots. These factors result in increased growth rates and increased yields when compared to tradition soil gardens where much lower oxygen and often nutrient levels are present.

2. Why is hydroponic gardening better than soil gardening?

Hydroponic gardening is better than soil gardening for several reasons. More plants can generally be grown in the same amount of space when compared to traditional soil gardens. Roots are delivered nutrients instead of having to stretch out in search of them. Also hydroponic gardens can be stacked to further increase space efficiency. The main benefit to hydroponic gardening is much higher oxygen levels in the root zone when compared to a soil garden. This increased oxygen means increased nutrient uptake and much higher rates of growth. It is also much easier to control the nutrient levels in hydroponic gardens compared to soil gardens.

3. Can I grow hydroponically outdoors?

Yes, Hydroponic gardens can be used outdoors. Some of the challenges may be keeping the nutrient solution at appropriate temperatures in hot or cold environments. In order to combat this, gardeners will employ the use of chillers and heaters. In situations where power is expensive or the gardener wants to use a more natural approach, reservoirs can be buried deep in the ground to regulate temperature. Root zone temperatures which are above 69° F can cause anaerobic bacteria to grow and harm the plants. Roots too cold will slow plant growth.

4. Can I grow organically with hydroponics?

Yes, there are many organic nutrients available for use in hydroponic gardens. A good one is Dutch Nutrient Formula’s Hydro Organic line. More care will be needed to ensure a clean system when using organics for hydroponics.

5. Are all types of plants suitable for hydroponic gardening?

Most plants grow well in hydroponic applications, although some are more difficult than others. Some plants such as varieties that product bulbs are better suited for soilless mediums than they are for say deep water culture. However, almost every plant that grows from seed will excel in a hydroponic garden.

6. Can I grow different plants in the same hydroponic system?

Yes, however it may be difficult to satisfy the nutritional requirements of different plants in the same system. Gardeners are best off to grow similar plants in one system or even a mono crop (all of the same). It is possible to grow green leafy vegetables in one system for example and tomatoes or flowering vegetables in another. The more variation between plants in a system, the more difficult it is to accommodate.

7. What size pump do I need for my Flood and Drain system?

A good general rule of thumb is: • 170 GPH water pump for a 4’x4’ Flood and Drain tray. • 300 GPH water pump for 4’ x 8’ Flood and Drain tray

Lighting FAQ
1. Can I use natural sunlight to grow plants indoors?

Yes, some gardeners take advantage of natural sunlight either in the greenhouse, beside a window or even by using skylights and solar tubes to light their gardens. Just be careful not to interrupt your plants dark cycle if it requires uninterrupted darkness.

2. What is High Pressure Sodium lighting and what is it good for?

A High Pressure Sodium light is a gas-discharge lamp that uses sodium in an excited state to produce light. HPS lamps have been the standard in indoor gardening for many years due to their ability to produce high intensity light in the red and orange color spectrums. This light is ideal to trigger a flowering response in flowing plants. This type of light has been shown to create large yields of high quality fruit and flowers. The downside to these lamps is the inefficiency of the lamps which can be noticed by the amount of heat that they produce. They also produce most of their light directly beneath the lamp making them more ideal for fewer large plants compared to many smaller plants as dispersing the light in an even pattern can be very difficult. With today’s technology growers are starting to employ the use of more efficient Induction Lamps and well as LED grow lights to more evenly disperse their light and lower the need for large ventilation or air cooling systems.

3. What is the difference between Digital and Magnetic HID ballasts?

Magnetic ballasts are the older type of HID ballast. They are constructed with a core and copper coil. They typically run very hot and emit a hum or buzzing sound during operation. They are typically only able to fire one type of lamp, either MH or HPS. There are however conversion lamps for magnetic ballasts that allow the opposite lamp type to be used (HPS in MH ballast or vise versa). Newer magnetic ballasts are switchable between lamp types. Digital ballasts run much cooler than magnetic ballasts. They also are more efficient; meaning more of the power consumed is used to produce light rather than heat. They have several other benefits such as soft starting lamps, a convenient dimming feature and most importantly the ability to run either MH or HPS lamps on both 120v and 240v power supplies. They are also much lighter than their magnetic counterpart so shipping can be much cheaper.

4. What types of lighting are suitable for indoor gardening?

There are several types of lighting all suitable for use in an indoor garden. Each has its advantages and disadvantages. The main types of garden lighting are:

  • Fluorescent
  • Induction
  • L.E.D
  • Metal Halide
  • High Pressure Sodium
  • Sulphur Plasma
5. What is a conversion lamp?

Conversion lamps are less popular these days due to switchable ballasts and digital ballasts which auto detect and fire both types of HID lamps. However, in a situation where you are running a magnetic HID ballast and want to run the opposite lamp than when your ballast is rated for, you are able to use a conversion lamp to accomplish this. Conversion lamps are typically more expensive than a standard MH or HPS lamp.

6. What is Fluorescent lighting and what is it good for?

A fluorescent lamp, fluorescent tube or compact fluorescent lamp is a very low pressure mercury-vapor gas-discharge lamp that uses a fluorescence to produce visible light. The electric current (in the gas) excites mercury vapor which produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful light much more efficiently than incandescent lamps. The most popular fluorescent lamps used for plant growth are T5 Fluorescents and Compact Fluorescents. When comparing the two of equal wattage, the T5’s are better for spreading out the light and covering a larger area more evenly. This is ideal for many small plants such as seedlings or cuttings. The CFL is better for covering a smaller area more intensely, which would be better for growing fewer, larger plants. When comparing Fluorescent lighting to other types of pant lighting, Fluorescents tend to excel at growing seedlings and cuttings as well as any plant with a low light requirement. Although possible, flowing fruits and vegetables is generally more successful with a higher intensity lamp.

7. Do I need a reflector?

Generally speaking a reflector is a must to ensure that all of your light is director towards your plants. Since lamps often produce light in a 360 degree pattern from the center of the lamp, it is especially important in horizontal applications to direct the light sent upward back down towards the canopy. A different style of growing employs the use of HID lamps hung vertically between taller plants. Since the lamp is hanging at approximately half way up the height of the plant and is surrounded by plants on all sides the reflector is not required. This is the only style of growing that will not benefit from the use of a high quality reflector.

8. What is an Induction Lamp and what is it good for?

An electrode less lamp or induction light is a light source in which the power required to generate light is transferred from outside the lamp envelope to inside via electromagnetic fields, in contrast with a typical electrical lamp that uses electrical connections through the lamp envelope to transfer power. There are three advantages of eliminating electrodes: • Extended lamp life, because the electrodes are usually the limiting factor in lamp life. • The ability to use light-generating substances of higher efficiency that would react with metal electrodes in normal lamps. • Improved collection efficiency because the source can be made very small without shortening life, a problem in electroded lamps Induction lamps are ideal for applications where low heat output and highly efficient lighting are required. Induction lamps provide similar light output to a standard fluorescent, except with a more optimized spectrum for plant growth and come in much higher wattages. Although initially a 400w Induction Lamp may appear to have similar performance to 400w of T5 Fluorescents (both producing approx 40 000 Lumens) the differences become evident very quickly. Induction lamps are rated for 10 x the bulb life than a T5 Fluorescent. This means the difference between 10 000 hours and 100 000 hours of bulb life. The induction lamp also maintains 90% of its light output over 70 000 hours. Like other fluorescent technologies, the induction lamp is not a High Intensity Discharge lamp, which means it produces its light over a larger surface area instead of being very intense in one hot spot. This means these lights evenly light a large area much more effectively than an HID lamp would. Huge savings can be realized when comparing to HID lighting by producing similar or higher light levels over a larger area while consuming less than ½ the wattage. (400w induction vs. 1000w HID.) The ideal distance between an induction lamp and plants is 6” vs. 18” for a 1000 HID. This means these lights excel at growing many short plants vs. few taller plants. Modern greenhouses are starting to employ the use of Induction lighting due to their excellent efficiency and length of operation.

9. Is it safe to run a 1000w Lamp on my homes current wiring?

Without knowing your particular electrical situation we cannot provide you with a definite answer. A qualified electrician should always be consulted when you are unsure of your wiring. Assuming your home is up to current electrical codes, assuming you have nothing else running on the circut, a 1000w HID would run safely on a standard 15 amp circut. A 1000Watt Light will use around 10 amps of electricity. Generally speaking, a standard household circuit in North America consists of 14 gauge wire rated for 15amps and 120v. Assuming that your 1000w light is the only thing plugged into that circuit, you will be drawing roughly 9.7 amps on the 15 amp circuit. This is below the 80% maximum load one should place on any electrical circuit and you would be safe to run your lamp. Exceeding the 80% capacity of any electrical circuit is not recommended and may be a fire hazard.

10. What is Metal Halide lighting and what is it good for?

A metal-halide lamp is an electric light that produces light by an electric arc through a gaseous mixture of vaporized mercury and metal halides[1][2] (compounds of metals with bromine or iodine). It is a type of high-intensity discharge (HID) gas discharge lamp. Developed in the 1960s, they are similar to Mercury vapor lamps, but contain additional metal halide compounds in the arc tube, which improve the efficiency and color rendition of the light. Metal halides are extremely efficient at producing light in the white and blue color range. These types of light have an ideal effect on vegetative plants. Using a metal halide for vegetative growth will produce short and bushy plants with extremely tight internodal spacing. The downsides to Metal Halide lights would be high operating temperature making exhaust fans or air cooled light fixtures a requirement, short bulb life (5-15 000 hours) and a rapid decrease in light output over the life of the lamp.

11. What is a relay or a flip box?

Relays or Flip boxes allow gardeners to divert the power from one ballast to a second reflector/lamp when the primary reflector/lamp is not in use. This means you can run your lamp and reflector for 12 hours and then use the relay to switch to a second garden for 12 hours. The benefit of these systems is doubling your garden space without purchasing a second set of ballasts. All that is required is a second lamp cord, reflector and lamp. Your ballast will run for 24 hours a day between both gardens. This does not work for 18/6 light schedules.

12. What is L.E.D. Lighting and what is it good for?

An LED lamp (or LED light bulb) is a solid-state lamp that uses light-emitting diodes (LEDs) as the source of light. LED lamps offer long service life and high energy efficiency, but initial costs are higher than those of fluorescent and incandescent lamps. Chemical decomposition of LED chips reduces luminous flux over life cycle as with conventional lamps. In regards to plant growth, LED grow lights employ the use of diodes producing only the specific wavelengths of light required for plant growth. This results in an extremely efficient grow light which can produce tremendous growth with minimal wattage. This makes LED grow lights ideal for situations where low temperatures and high efficiency are a must. In small scale gardens where it is difficult to run a HID lamp due to excessive heat, LED grow lights are a viable alternative. Modern greenhouses are starting to employ the use of LED lighting due to their excellent efficiency and length of operation.

13. Are there controllers available to run multiple HID lamps from one power source?

Yes, gardeners can purchase pre-made lighting controllers that require a dedicated wire to an electrical panel or other high power outlet (dryer or stove outlets). This allows you to plug your multiple hid lamps into one controller and use one timer to control the light schedule of all of your lights. This is the simplest way for a gardener to run multiple HID lamps. These Power Boxes can be purchased at any Homegrown Hydroponics location.

14. What is Sulphur Plasma lighting and what is it good for?

The sulphur-plasma lamp is a relative newcomer, but it shows some promise where very high intensity lighting is needed. The primary light source is a small quartz bulb with a few milligrams of sulphur inside (along with an inert gas – typically argon or xenon), and this is subjected to intense bombardment with microwave energy. After a few seconds, the sulphur starts to convert to the fourth state of matter – plasma. Full intensity is reached in less than 5 minutes. The plasma principle is used for most HID lamps, except that the others (metal halide, mercury vapour, high pressure sodium, etc.) use electrodes inside the tube, rather than bombarding the active material with microwave energy. Ultimately, it is largely the erosion of the electrodes (along with possibly broken high pressure seals between the envelope and the electrode lead-in wires) that signals the end of life of a typical plasma light source. • Sulphur bulbs are twice as efficient as other sources of high quality white light. • They produce almost no ultraviolet light and very little infrared; this makes them easier to use with plastic fixtures or fibres. • The full-spectrum light that is produced is extremely good for visual acuity and feels much like sunlight. • The bulb is very simple, a hollow quartz sphere with sulphur and argon gas, and so it is environmentally benign and does not degrade in use. • The light source is very bright so the light can be efficiently distributed over large spaces. • The light output and colour does not degrade over time, and it is fully dimmable down to 30%. The downside to Sulphur Plasma lighting is that it is cost prohibitive. With many companies failing to successfully launch this new technology, the high cost (approximately $3500 per 1000w unit) is surely a huge factor.

15. Is it safe for my eyes to look at grow lights?

No, one should never look directly into a grow light. This can cause serious injury to your retina. It is however acceptable to work in areas lit by HID lighting. Some gardeners feel their eyes become strained after prolonged exposure to HID light environments. All gardeners would benefit from eye protection when working around indoor grow lights. The benefits are protecting your eyes from damaging UV rays as well as correcting the color emitted by HID lights to a more natural appearance for easier disease pest identification. The sooner the gardener can spot problems, the more effectively they can be dealt with. One ounce of prevention is worth a pound of cure! Method Seven protective eye wear is available at all Homegrown Hydroponics locations.

16. How much light do I require?

Plants with the highest light requirements will grow best with HID light levels between the ranges of 40w-75w per square foot of garden area. This means that when using a Metal Halide or High Pressure Sodium grow lamp the gardener would use: 1000w to cover a 4’x4’ area. 1000w/16 sqft = 62.5 w/sqft 600w to cover a 3’x3’ area. 600w/9 sqft = 66.7 w/sqft 400w to cover a 2.5’x2.5’ area. 400w/6.25 sqft = 64 w/sqft. In confined spaces such as grow tents; gardeners will often go one size down in order to more easily keep temperatures in the desired range for optimal plant growth. I.e. 2 x 600w in a 4’ x 8’ tent rather than 2x 1000w. Some plants (especially the non flowering varieties) can grow fine with 20-45 watts per square foot. When calculating the required amounts of fluorescent lighting for seedling, cutting or any vegetative growth of small plants, roughly half of the recommended HID wattage is required to promote this early growth. I.e. 400w t5 fluorescents over a 4’x4’ area.

17. How do I dispose of old grow lamps?

Due to the contents of hazardous metals found in grow lamps, they should be recycled properly by taking them to your local recycling depot. Some hydroponic stores will recycle them for you as well. Grow lamps should not be placed in the garbage as they are likely to break and leak their contents into the ground at the landfill.

18. How long should I leave my grow lights on for?

Some gardeners like to leave their lights on for 24 hours to get maximum growth. However, by far the most popular light duration for vegetative plants is 18 hours on and 6 hours off. This schedule will mimic a day of full sunshine followed by a natural dark period. Using this method will save the gardener electricity while still providing exceptional growth. Some plants are triggered to flower by a reduced duration of daylight. These plants can be tricked indoors into producing their flowers with a reduction of light duration. To achieve this, most gardeners will reduce their light to 12 hours on and 12 hours off. Other plants simply flower then they are mature and can benefit from the 18 hours of light throughout their life.

19. How far should my light be from my plants?

Low heat grow lights such as fluorescent and induction lamps should be kept approximately 6” from the tops of plants for optimal growth. LED grow lights can usually be kept at a distance of 9”-12” from the tops of plants for optimal growth. 400w HID should be kept at a minimum of 12”-16” inches from the tops of plants for optimal growth. 600w HID should be kept at a distance of 16”-20” inches from the tops of plants for optimal growth. 1000w HID should be kept at a distance of 18”-24” inches from the tops of plants for optimal growth. Often lamps used in conjunction with an Air Cooled Reflector can lead to a decrease in distance required distance between lamp and plants. Using ones hand at plant height to determine the amount of heat between the lamp and the plant is an effective tool at gauging light heights. If the temperatures are comfortable for your hand then they are comfortable for the plants.


Insect and Fungus FAQ
1. What types of insects might attack my plants?

A variety of insects may be attacking your plants. Some that you may encounter are: •Spider Mites •Thrips •Aphids and Root Aphids •Mealy bugs •Fungus gnats •White Flies

2. I see spiders in my grow room, are they bad for my plants?

No, spiders are not bad for your plants. In fact they will eat many other insects which may harm your plants.

3. How can I prevent insects from getting into my grow room in the first place?

The best way to prevent an insect infestation is to take some precautions. Intake filters are a must. If you cannot find them at your local gardening store, furnace filters are the second choice and can be adapted well. The gardener should also wear clean clothes when entering the garden. Never work in an outdoor garden and then enter your indoor garden. This is a sure way to transfer pests to an indoor garden. Changing shoes is also a good practice as many pests can be tracked in that way. Pets should not be allowed to enter the indoor garden as they can also carry pests in their coat. Sealing gaps and cracks will also go a long way towards preventing unwanted pests from entering the sterile garden environment. Any new plants entering the garden should first be kept in quarantine for at least one week if not longer, where they can be examined. Once they are determined to be insect free, they can then be introduced safely into the garden.

4. I see bugs on my plants, what can I do about it?

There are several ways to deal with insects in the garden. Insecticides containing Pyrethrins are a good way to kill most insects on contact. They come in aerosol cans as well as concentrated forms that can by mixed in a sprayer. The active ingredient is derived from the Chrysanthemum flower making it a natural insecticide. It has a short half life so it is not very toxic to humans. When applying the aerosol varieties only small burst of product should be applied from several feet away from plants to avoid soaking them and causing damage. Only a small amount of the product is necessary to kill insects on contact. As with any insecticide several applications should be done to kill any insects that may hatch from eggs after the initial application. Usually repeating application ever 5-7 days is a good rule of thumb, however each insect has a different life cycle and higher temperatures dramatically speed up insect reproduction rates. Pyrethrins are known to be effective at combating Aphids, Spider Mites, Whitefly’s and exposed Thrips amongst other insects. Diatomaceous Earth or DE is a powdered insecticide comprised of microscopic crustaceans. These crustaceans are extremely jagged and actually cut through the exoskeleton of the insect causing them to dehydrate. This makes DE a very effective contact insecticide. It can be applied to the growing medium, dusted onto plants or spread around the grow room to kill any insects on contact. It is safe for human contact and is even consumed orally as a natural cleansing product. Another approach is to use natural predator insects to hunt down and eliminate the pesky insects you are dealing with. Every insect has a specific predator which are most effective at eliminating them. Lady Bugs are good all purpose predators and are stocked at all Homegrown Hydroponics locations.

5. How do I determine which type of insect I am dealing with?

The best way to identify the insect which is attacking your plants is to capture a specimen and examine it under a microscope or magnifying glass. This will aid tremendously in indentifying the pest as most insects that damage plants are very small. Once you have a good look at the culprit, compare with a book or online reference of garden pests to find its identity.

6. Are there natural predators that I can use to eliminate an insect infestation?

Yes, natural predator insects can be utilized to hunt down and eliminate the pesky insects which are damaging your garden. Every insect has a specific predator which is most effective at eliminating them. Lady Bugs are a good all purpose predators and are stocked at all Homegrown Hydroponics locations. Specific predators can be ordered by request.

7. I know I have spider mites, but I can’t seem to get rid of them! What should I do?

The two most common barriers to ridding a garden of spider mites are using only one type of insecticide which they may become resistant to as well as not applying your insecticides at the correct intervals. Alternating insecticides is all it takes to get past the resistance problem and doing at least three applications an average of 5 days apart should also interrupt the reproduction of the mites as well as kill any eggs that hatched after the first or second applications. Whenever a Spider Mite outbreak has occurred, the entire garden should be sterilized after harvest by spraying down and scrubbing all surfaces with a bleach water solution and or employing the use of an insecticide “bomb” or total release fumigator. The total release fumigator is a can of insecticide which can be opened and placed into the sealed garden where it will release all of its contents. The garden is left sealed with this insecticide for two hours before it is ventilated. All insects should be eliminated with one application.

8. There is a white powder on my leaves, is it bad for the plants?

This is most likely Powdery Mildew and it will damage you plants. Powdery Mildew spores are present virtually everywhere. When conditions become favorable for it to colonize, it will do so on your plants. Lowering humidity and having good circulation are good preventative measures. Once you have the problem, there are several fungicide products which can be applied to the leaf surface to eliminate the mildew. Safer’s Defender and Serenade are two effective treatments sold at all Homegrown Hydroponics locations.

9. My leaves have black and rusty spots on them, what’s wrong?

Similar to powdery mildew, black spot is a fungal infection of the leaf tissue. Lowering humidity and avoiding getting water directly on plant leaves are the best ways to avoid this problem. If it does start to occur on your plants, several garden fungicides are known to be effective at treating the issue.

10. My flowers have a black/grey fuzz growing on them, what’s wrong?

This is a fungal problem that occurs when flowers are in areas of high humidity or when they do not dry off after being wet from rain or watering. Keeping the humidity of the garden below 50% and ideally around the 40% range during flowering will often eliminate this problem. Certain moist areas can develop in a garden when air circulation is poor. Ensuring proper air circulation and lowering humidity levels will often eliminate this flower rot. In outdoor gardens there is unfortunately not much that can be done to lower the humidity and to dry plants out faster after heavy rainfall. This often becomes a problem with outdoor crops in the autumn when rain is frequent and day temps are not warm enough to thoroughly dry off plants. These prolonged periods of moisture often cause flowers to rot. If possible the gardener should try to spread apart the branches of their plant to improve airflow around the flowers.


Water And Nutrients FAQ
1. Why do I have to adjust the pH of my nutrient solution?

Why do I have to adjust the pH of my nutrient solution? A: Soil has a good capacity to buffer pH. This means that when the pH level of water is not ideal, the makeup of the soil acts as a buffer and balances out the pH of the incoming water to generally an acceptable level. It is important to adjust the pH of a hydroponic nutrient solution because there is no soil to act as a buffer and correct an improper pH level. It must be done manually adding pH up or pH down to the water after the nutrient has been added to the solution. Setting pH to the correct level will allow the plants to uptake all of the nutrients required for optimum growth.

2. Do I need to use distilled or RO water for hydroponics?

No, it is not absolutely required to run Reverse Osmosis or Distilled water for hydroponic gardens. However, a percentage of your plants feed will consist of whatever minerals are found in your water. Most water still works well, but in some cases or when the gardener is looking for complete control of the nutrients their plants are consuming purified water may be the best option. It is often necessary to replenish the Calcium and Magnesium levels in purified water to form a complete nutrient solution. Botanicare’s Cal-Mag supplement is carried by all Homegrown locations. It is also very difficult to stabilize the pH of purified water due to its lack of minerals to buffer the pH. The addition of Cal-Mag will help solve this issue.

3. What is the ideal pH level?

Generally in a hydroponic application plants should be kept between pH of 5.5 and 6.2. In a peat based soilless medium 6.2 tends to be an ideal level. In soil most plants excel anywhere in the pH range of 6 to 7. If the plant you are growing is not an acid loving plant, it will do better at a pH slightly higher than 7.0

4. Is my well water okay for growing plants?

Without seeing an analysis it is impossible to answer this question. Often well water is very hard and should be used in conjunction with a nutrient line which has been specially formulated for use with hard water. The other option would be to run the well water through a Reverse Osmosis system to remove the excessive minerals.

5. My pH keeps fluctuating, what’s going on?

So you set the pH of your hydroponic reservoir to 5.5 only to return 2 days later to find the level has risen to a pH of 6.0! You’re wondering why the pH won’t stay where you set it? The nutrients you add to your reservoir are acidic. When the plant consumes these acidic nutrients, the natural reaction is a rise in pH. This means it is normal for your reservoir to have a natural pH up-swing. It is much more desirable than your pH dropping, which would indicate you have too much nutrient in your solution. Here is a cheat sheet: pH goes up, EC goes down = Plants are feeding. Potentially raise nutrient levels. pH goes down, EC goes up = Plants are putting nutrient into the water rather than taking them out. Nutrient levels are too high. pH stays stable, EC levels stay stable = Equilibrium. Plants are taking equal parts nutrients and water. Maximum growth is occurring. It is best to error on the side of caution and slightly underfeed you plants . This will encourage the natural pH swing from 5.5-6.2. Once your solution reaches the 6.2 mark it should be brought back down to 5.5 pH and allowed to slowly drift up again. The reason this is ideal is that the plants are able to take up specific nutrients more efficiently at different pH levels. By going up and down through the proper pH range the plant has good access to all nutrients required for optimal growth. Having the ability to monitor and adjust nutrient and pH levels in this fashion are one of the main benefits to an active or recirculating hydroponic system.

6. What is a good fertilizer to use for growing plants?

There are many good fertilizers available on the market for aiding in plant growth. However, when a gardener is growing hydroponically it is essential that they use a complete hydroponic nutrient such as the Dutch Nutrient Formula. The key things to look for in a premium hydroponic nutrient are a 2 part solution to prevent minerals from binding and no longer being available to the plant, an affordable nutrient, an easy to use nutrient and a nutrient that is complete with both micro and macro nutrients. Everything your plant requires for optimal growth should be contained in those two bottles. A premium nutrient will also have specific nutrients from the growth and flowering stages of plant life.

7. How much air is required to aerate my nutrient solution?

In a Deep Water Culture hydroponic system, it is absolutely crucial to have adequate oxygen levels because roots are submerged. For optimal growth it is recommended to have 1 Litre Per Minute of air pumped into each Gallon of nutrient solution. Therefore a 100 Gallon reservoir would require a 100 LPM air pump for maximum oxygenation. In every other hydroponic application it is only required to oxygenate the solution enough to prevent it from becoming anaerobic. This means much less air is required. Generally if you have good movement in the solution and the majority of the surface of the solution is broken with bubbles you should be fine. Roughly ¼ – ½ the oxygenation rate of a DWC system should be more than adequate. It is possible to have too much aeration because the bubbles coming out of the air stone or diffuser create friction. The more friction produced, the more heat produced. So in some cases adding more aeration can be counterproductive. Water temperatures also affect the amount of oxygen that water can hold. Excessive reservoir temperatures will prevent sufficient oxygen saturation levels. For this reason it is not recommended to exceed 68 Degrees Fahrenheit in your nutrient reservoir.

8. What strength fertilizer do I use for different stages of plant growth?

Most established plants grow and produce very well with a max nutrient concentration of 2.2 EC. When plants are first starting out they should be fed quarter strength fertilizer once they produce their first sets of true leaves from seed, or once they show roots as cuttings. * Seedlings and Cuttings 0.5-0.7 EC * Medium plants 1.0-1.4 EC * Established plants 2.0-2.2 EC Plants grown with high light levels and supplemental CO2 can often exceed these levels.

9. Are organic fertilizers better than synthetic fertilizers?

In certain applications, yes. In outdoor or living soil applications it is beneficial for the gardener to use organic nutrients because they will contribute to building up a healthy and living soil environment full of beneficial microbes and fungi that will sustain plant growth for years to come. The addition of slow release or liquid organic feed will improve the health of the soil and contribute to plant growth accordingly. Alternatively, synthetic nutrients will still increase the production of crops in soil. However, the soil quality can be negatively affected by these synthetic fertilizers and the soils become dependent on repeated applications of synthetic nutrient. Scientifically speaking, when an organic nutrient breaks down with the help of enzymes produced by bacteria living in the medium, it becomes chemically identical to a synthetic nutrient. The plant is not able to tell the difference between whether its nutrients were organically or synthetically derived. The difference lies is in the effect on the symbiotic relationship between the roots and the beneficial organisms living amongst them. Some gardeners feel that growing with organic nutrients will produce a better crop due to these organisms flourishing in the root zone. In hydroponic applications gardeners have the choice of using organic or synthetic nutrients with similar results. The synthetic nutrients generally give faster and more predictable results. Organic nutrients still produce excellent crops but can lead to more frequent cleaning of hydroponic systems and reservoirs.

10. How do I improve the performance of my outdoor soil gardens?

The best way to improve the performance of an outdoor garden is by amending your soil to improve its drainage, water retention and fertility. The addition of peat moss or coco coir will aid in fluffing up your mix which will increase the oxygen available to the root zone. Water retention should also be improved. The addition of premium organic slow release fertilizers will build up your soil quality for the long term, or faster acting liquid organic fertilizers can be used to increase soil fertility. Some of the most common additives to outdoor gardens are as follows: * Coco or Peat to improve aeration and water retention * Worm castings to provide growth hormones and nutrition * Kelp meal to provide micro nutrients * Volcanic and Glacial rock minerals to provide micronutrients and increase drainage * Premium organic additives such as Blood and Bone meal, Gypsum, Bat Guanos, Rock Phosphate, Alfalfa meal, Greensand, composted organic matter to add macro nutrients. * Dolomite Lime to buffer pH Some gardeners will produce compost teas out of these organic additives rather than working them into the soil. This allows the release of their nutrient much more rapidly for more immediate results.

11. What is Compost Tea and how do I make one?

Organic Teas or Compost Teas are teas made by combining organic additives with water and adding aeration to kick-start the decomposition process. The simplest way to produce a tea at home is to take a 5 gal pail (large pail) and fill it ¾ with de-chlorinated water. Next you add compost, worm castings or some other sort of organic fertilizer and some un-sulphured blackstrap molasses to the mix. You then connect an air pump to an air line with an air stone on the end and place the air stone in the pail as to oxygenate the solution. The result is rapid reproduction of the beneficial bacteria living in the organic matter due to the increased oxygen and carbohydrate food source. The organic matter gets broken down quickly which releases its nutritional content into the water. This process turns slow release organics into rapid acting organic fertilizer. A good recipe is as follows: * 5 Gal de-chlorinated water * 2 Cups Worm Castings * 2 Tbsp Bat Guano (veg or bloom depending on growth stage) * 1 Tbsp Humic Acid * 5 Tbsp Blackstrap Molasses (or other carbohydrate additive) * 1 Tbsp Kelp Meal * Bubble this for 24-48 hours until a frothy foam develops on the top of the pail * Dilute to 50% with a second pail of un-chlorinated water and pour or spray over plants

12. Why is a two part nutrient better than a one part nutrient?

Two part nutrients are superior to one part nutrients because they separate minerals which would otherwise bind together forming sediment in the bottle. These minerals can become permanently bound up and unavailable to plants. Keeping these nutrients separate when in concentrated form ensures a virtually unlimited shelf life and that 100% of the nutrient you are paying for is available to your plants.

13. How do I test my nutrient concentration?

The best way to test your nutrient concentration is with an EC meter. EC meters test the electrical conductivity of water, and give you an indication of of the strenghth of your nutrient solution. They work best with conventional mineral nutrients. EC meters are not as accurate for organic nutrients because not all the nutrients are in a form the meter can read. For more info, see our page about EC and Nutrients here.

14. What is the difference between EC, TDS and PPM. Which one should I use?

There are several tools available to test the Total Dissolved Solids present in a nutrient solution. Where it gets confusing is which units to display your values in. The most common are Electro Conductivity (EC) and Parts Per Million (PPM). EC is the best way to display the TDS of a nutrient solution because it is a universal unit. Unlike PPM which is EC x 0.5 or EC x 0.7. Since there are two different conversions of EC to PPM, PPM becomes an unreliable way to describe nutrient concentrations because you never know whether someone is using the same scale as you are. To break it down: * Electro Conductivity is displayed in EC or EC x 1000. * Parts Per Million is either EC x 0.5 or EC x 0.7 * Therefore 2.0 EC or 2000 EC = 1000 PPM or 1400 PPM depending on which conversion factor is used. 2000 EC x 0.5 = 1000 PPM or 2000 EC x 0.7 = 1400 PPM Seeing as how there are two different PPM values for the same EC value depending on conversion factor used, EC is a much better way to describe nutrient concentrations.



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