Aquaponics Grow Media

credit to : Farm Tech Mart
link : http://farmtech-mart.com/grow_media

Although there is no soil in a hydroponic garden, the plants must still be anchored. There is a wide range of inert materials which can be used to support plant roots and we call them "growing mediums". Clay Pellets, Perlite, Vermiculite, Coconut Fiber and Rockwool are the most popular media. The hydroponic media that work best are pH neutral, provide ample support for plants, retain moisture, and allow space for good air exchange. The type of media you choose will depend on the size and type of plants you wish to grow, and the type of hydroponic system being used. 

1. Clay Pebbles (LECA) 

Expended Clay Aggregate pebbles (LECA) main use is as a hydroponic growing media in flood and drain and dripper hydroponics systems like the Wilma. Clay pebbles can also be mixed with other hydroponic growing media like Cellmax, Coco or Soil to give better aeration. To create better drainage when growing in pots add a layer of Clay pebbles in the bottom.

Many growers use clay pebbles as a hydroponic growing media because they have excellent aeration and drainage properties. Clay pebbles are a clean, ph stable, and can be reused a couple of times before they need to be replaced.

Flood and drain or a dripper system will deliver the fast growth rates and yields using clay pebbles.

The centre of a clay pebble is honeycomb to make it light weight and the outside of a clay pebble is covered in a thin layer of solid clay making them suitable for use in hydroponics.

Tired of looking at dirty soil on the top of house plants in pots why not use some clay pebbles to make it look more attractive.

2. Perlite

Good old perlite! It's been around for years, mainly for use as a soil additive to increase aeration and draining of the soil. Perlite is a mined material, a form of volcanic glass that when rapidly heated to more than 1600 deg. f. it pops much like popcorn as the water vaporizes and makes countless tiny bubbles.

Perlite is one of the best hydroponic growing mediums around. Used by itself or as a mixture with other mediums. Perlite is commonly used with vermiculite ( a 50 - 50 mix is a very popular medium), and is also one of the major ingredients of soiless mix's. Perlite has good wicking action which makes it a good choice for wick-type hydroponic systems. Perlite is also relatively inexpensive.

The biggest drawback to perlite is that it doesn't retain water well which means that it will dry out quickly between waterings. The dust from perlite is bad for your health so you should wear a dust mask when handling it.

3. Vermiculite 

Vermiculite is another mined material. In it's natural state it resembles mica rock, but when quickly heated it expands due to the generation of interlaminar steam.

Vermiculite is most frequently used in conjunction with perlite as the two complement each other well. Vermiculite retains moisture (about 200% - 300% by weight), and perlite doesn't so you can balance your growing medium so that it retains water and nutrients well but still supplies the roots with plenty of oxygen. A 50/50 mix of vermiculite and perlite is a very popular medium for drip type hydroponic systems as well as ebb and flow systems. Vermiculite is inexpensive.

The major drawback of vermiculite is that it retains too much water to be used by itself. It can suffocate the roots of plants if used straight.

4. Coconut Fiber 

Coconut fiber is rapidly becoming one of the most popular growing mediums in the world. In fact it may soon be THE most popular. It is the first totally "organic" growing medium that offers top performance in hydroponic systems. Coconut fiber is essentially a waste product of the coconut industry, it is the powdered husks of the coconut itself.

There are many advantages - it maintains a larger oxygen capacity than rockwool, yet also has superior water holding ability than rockwool which is a real advantage for hydroponic systems that have intermittent watering cycles.

Coconut fiber is also high in root stimulating hormones and offers some protection against root diseases including fungus infestation. Dutch growers have found that a mixture of 50% coconut fiber and 50% expanded clay pellets is the perfect growing medium.

One word of caution about coconut fiber, you must be careful when you purchase coconut fiber. There is a commonly available, lower grade of coconut fiber that is high in sea-salt and is very fine grained. Lower grade coconut fiber will lead to disappointing results when used in a hydroponic system.

5. Rockwool

Rockwool is a very popular hydroponics growing medium. Rockwool is a porous substance that forms when a mixture of rocks, mostly basalt and dolomite, is melted at high temperature and specially processed. Given the material's neutral nature, it is used to build plant-growing medium granules or slabs, blocks, plugs, cubes, etc.

Rockwool provides roots with a good balance of water/oxygen As rockwool is composed of 97% air, it is easy to control the air/water ratio in it. Its porous quality also enhances root growth.

. Small cubes are used for starting seeds and cuttings, 3" or 4" cubes for small plants or intermediate growth, and slabs for larger plants. Rockwool can be used with continuous drip or flood and drain systems. Although it is possible to sterilize and re-use Rockwool, most often it is used only once.

More than 95% of all greenhouse vegetable production is carried out with the help of Rockwool -and for good reason. Like mentioned before, rockwool allows control over air and water supply, which are essential factors for plant growth. It also provides other feasible conditions to support a great crop, leading to consistency in plant production and yield, which is an important consideration in commercial harvesting.

Another pro is the easy availability of Rockwool products in a variety of shapes and sizes. This promotes the maximum utilization of Rockwool in various types of hydroponic set-ups.

Aquaponics Organic Pesticide

Neem oil
From Wikipedia, the free encyclopedia

Neem oil

Neem oil is a vegetable oil pressed from the fruits and seeds of the neem (Azadirachta indica), an evergreen tree which is endemic to the Indian subcontinent and has been introduced to many other areas in the tropics. It is the most important of the commercially available products of neem for organic farming and medicines.

Neem oil varies in color; it can be golden yellow, yellowish brown, reddish brown, dark brown, greenish brown, or bright red. It has a rather strong odor that is said to combine the odours of peanut and garlic. It is composed mainly of triglycerides and contains many triterpenoid compounds, which are responsible for the bitter taste. It is hydrophobic in nature; in order to emulsify it in water for application purposes, it must be formulated with appropriate surfactants.

Azadirachtin is the most well known and studied triterpenoid in neem oil. The azadirachtin content of neem oil varies from 300ppm to over 2500ppm depending on the extraction technology and quality of the neem seeds crushed. Neem oil also contains steroids (campesterol, beta-sitosterol,stigmasterol).

Neem fruit

The method of processing is likely to affect the composition of the oil, since the methods used, such as pressing (expelling) or solvent extraction are unlikely to remove exactly the same mix of components in the same proportions. The neem oil yield that can be obtained from neem seed kernels also varies widely in literature from 25% to 45%.

The oil can be obtained through pressing (crushing) of the seed kernel both through cold pressing or through a process incorporating temperature controls. Neem seed oil can also be obtained by solvent extraction of the neem seed, fruit, oil, cake or kernel. A large industry in India extracts the oil remaining in the seed cake using hexane. This solvent-extracted oil is of a lower quality as compared to the cold pressed oil and is mostly used for soap manufacturing. Neem cake is a by-product obtained in the solvent extraction process for neem oil.

Neem leaves and flowers

Neem oil is not used for cooking purposes. In India, it is used for preparing cosmetics (soap, hair products, body hygiene creams, hand creams) and in Ayurvedic, Unani and folklore traditional medicine, in the treatment of a wide range of afflictions. The most frequently reported indications in ancient Ayurvedic writings are skin diseases, inflammations and fevers, and more recentlyrheumatic disorders, insect repellent and insecticide effects.

Traditional Ayurvedic uses of neem include the treatment of acne, fever, leprosy, malaria, ophthalmia and tuberculosis. Various folk remedies for neem include use as an anthelmintic, antifeedant,antiseptic, diuretic, emmenagogue, contraceptive, febrifuge, parasiticide, pediculocide and insecticide. It has been used in traditional medicine for the treatment of tetanus, urticaria, eczema,scrofula and erysipelas. Traditional routes of administration of neem extracts included oral, vaginal and topical use. Neem oil has an extensive history of human use in India and surrounding regions for a variety of therapeutic purposes. Puri (1999) has given an account of traditional uses and therapeutic indications and pharmacological studies of this oil, in his book on neem.

Formulations made of neem oil also find wide usage as a biopesticide for organic farming, as it repels a wide variety of pests including the mealy bug, beet armyworm, aphids, the cabbage worm, thrips, whiteflies, mites, fungus gnats, beetles, moth larvae, mushroom flies, leafminers, caterpillars, locust, nematodes and the Japanese beetle. Neem oil is not known to be harmful to mammals, birds, earthworms or some beneficial insects such as butterflies, honeybees and ladybugs if it is not concentrated directly into their area of habitat or on their food source. It can be used as a household pesticide for ant, bedbug, cockroach, housefly, sand fly, snail, termite and mosquitoes both as repellent and larvicide. Neem oil also controls black spot, powdery mildew,anthracnose and rust fungi.

Neem seed oil has also been found to prevent implantation and may even have an abortifacient effect similar to pennyroyal, juniper berries, wild ginger, myrrh and angelica. The effects were seen as many as ten days after fertilization in rats though it was most effective at no more than three days. (Sinha, et al., 1984); (Lal et al., 1985). In a study on rats, neem oil was given orally eight to ten days after implantation of the fetus on the uterine wall. In all cases, by day 15, the embryos were all completely resorbed by the body. The animals regained fertility on the next cycle showing no physical problems. Detailed study of the rats revealed increased levels of gamma interferon in the uterus. The neem oil enhanced the local immune response in the uterus.(Mukherjee, 1996) Post coital use of neem oil as birth control does not appear to work by hormonal changes but produces changes in the organs that make pregnancy no longer viable (Tewari, 1989),(Bardham, 1991).

Neem seed oil has also been used as a renewable source for the preparation of polymeric coatings. It has been converted into various polymeric resins, including polyesteramides and polyetheramides. These resins may be utilized further for preparation of polyurethane coatings.

Neem tree

Aquaponics & Mosquitoes - Lesson Learnt

credit to http://www.friendlyaquaponics.com/

from the post : Welcome to “The End of Malaria”

Are you irritated by mosquitoes in your neighborhood? Do you live in a location where malaria, elephantiasis, filariasis, dengue fever, or any of the other dangerous diseases carried by mosquitoes exist? Are you a health-care professional whose concern is these diseases and their control and eradication? If the answers to these questions interest you, please read on:

An additional benefit of farming aquaponically (that we noticed after our first system was operational for six months) was that the mosquitoes on our seven-acre farm had COMPLETELY disappeared! We live in Hawaii, where there are as many mosquitoes as any other tropical area in the world. Although we are fortunate not to have malaria, elephantiasis, filariasis, or any of the other dangerous diseases that are transmitted to humans by mosquitoes, we DO have dengue fever, which can be fatal in the young, elderly, or those with compromised immune systems.

Before we built our first aquaponics system, our farm was like any other place on the green windward coast of the Big Island: even during a drought, when the soil was dusty and dry and there was no standing water visible anywhere, there were still clouds of mosquitoes at dawn and dusk. If we left a door or window open in the house during the day, even for a few minutes, we knew that we would be tormented by the buzzing of hungry mosquitoes all night long as we tried to sleep. When we built our first aquaponics system, we knew we were creating additional habitat for mosquitoes to lay their eggs, so we introduced a few mosquito fish (gambusia affinis), and neon tetras into our system water.

They thrived and spread throughout the systems we built, and soon had become a self-sustaining population numbering in the tens of thousands. Six months later we noticed there were simply no mosquitoes around any longer. It’s easier to notice the presence of a pest than the absence of one, so we’re not certain when the number went to zero, but it was sometime during that six-month period. That was three years ago Since then, we’ve had the pleasure to live on a beautiful farm in the tropics that has NO mosquitoes! How does this work?

We live in the center of a deadly efficient mosquito trap: every female mosquito in the neighborhood can sense the roughly 50,000 gallons of water in our aquaponics systems, and comes to them to lay her eggs. Each egg hatches into a larva, which is then promptly consumed by one of the hundreds of thousands of mosquito fish in our water BEFORE it can ever develop sufficiently to hatch into an adult mosquito. That mosquito’s bequest of future generations is GONE, down the gullets of little fish who thrive on these meals and produce even MORE little fish hungry for mosquito larvae.

We don’t know what the effective radius of our mosquito eradicator is, but we’ve gone to the corners of our seven-acre property and haven’t found any mosquitoes there; we think there’s a good chance it is significantly reducing mosquito populations on the farms around us. We need help and funding to continue research into this phenomenon in order to understand it better, and to develop it to the point where it can easily be implemented in any location or culture.

This could make a huge difference in the lives of people worldwide who currently lose family members to malaria and other mosquito-borne diseases.