Jul 18

Occupy Your Flat Rooftop With Aquaponics.

DVD How To Build Aquaponics. Click here!


Do you have a flat rooftop on your high rise apartment building, community center, high rise car park or school?

Do you have basic construction skills, know how to use a saw and a hammer?

Does your roof have at least 600 kilos per square metre weight loading tolerance? (This is important, water is HEAVY, although not nearly as heavy as wet soil, which contains rocks as well).

OCCUPY YOUR FLAT ROOFTOP WITH AQUAPONICS and start your aquaponic farm up there in the city where the demand for food is.

You can adapt your roof with fish tanks and hydroponic raceways that hold only water and grow far more food than any soil farm can grow on an equivalent limited space.

Do your homework properly and get permission and a community of growers together BEFORE you occupy your flat rooftop. Your flat rooftop is either the property of the person who lives beneath it or the property of the building’s owner.  You don’t want your aquaponic farm thrown off your flat rooftop into the street or a court order forcing you to demolish it. Make sure your flat rooftop is really able to support the total weight of your aquaponics systems before you occupy it.

Once you have got permission, there is a lot of planning and thought that has to go into designing and costing your aquaponics systems before you occupy your flat rooftop. A lot of the information about how aquaponics works and how costing works out is here to download for free:

AQUAPONICS LIBRARY.

I have also put together an over 30 chapter collection of posts from this site about many aspects of aquaponics as  ‘Aquaponics Global Anthology 1‘ which you can download instantly to print out from here:

[paiddownloads id=”1″]

DVD How To Build Aquaponics. Click here!

There is also a very good DVD with clear diagrams of how to plumb in the pipework of your rooftop aquaponics system:

Jun 20

Aquaponics And Green Walls

green wall

Vertical green wall construction

Ornamental green walls on buildings have got quite a bit of attention recently. I was trying to get into the Queen’s Jubilee parade recently in London when I came across one of them on Park Lane, near Marble Arch.
Of course, everything growing up the building was ornamental, not edible.
It occurred to me that there are thousands of square miles of indifferently insulated external walls on high rise buildings that could be adapted fairly cheaply to growing EDIBLE aquaponic green walls.  These could easily be watered in a cascade system recirculating water from the bottom to the top of the building, using waste water from fish rearing tanks on the roof and/or in the basement of the building.

All you would need would be a couple of low-wattage aquaculture pumps such as the Sweetwater range. This would take urban farming to a new level, installing aquaponic farms all over vertical and near-vertical surfaces all over the city.

Systems of suspended platforms similar to what are already used to clean windows on these buildings could be used to harvest the crops from the aquaponics green walls.

Climbing squash

Climbing squash

Bumper crops of vining plants such as bean varieties, including soybeans, tomatoes, peppers, melons, squash, strawberries, passionfruit, and so on could be got off these vertical  surfaces. Aquaponics marries aquaculture and hydroponics, and green walls are a form of hydroponics gone vertical, which can definitely use the waste water from fish farms for nourishment for these crops.

The rooting surface would be a thick layer of coir (coconut fibre) matting stapled under a plastic mesh. The water would be piped to cascade down the building’s sides through the coir matting, to be collected in gutters at the bottom. From there it would flow using gravity to a sump to be pumped back to the fish tanks.

The usual aquaponic filtration units would stand between the fish tanks and the vertical green walls, to collect fish solids that would otherwise cause clogging and odour problems.  The plants would take up the nitrates from the fish and the water would go back to the fish tanks clean, to be reused.

Vertical hoop houses could be installed to provide winter cover and extend the growing season on the edible green walls. In tropical urban farms on these vertices, winter protection would not be necessary.

Solar and wind energy could be used to power the pumps, based on the roof.  This can be tied into heat pumps recycling heat from inside the building, heat going to waste from air conditioners, etc, which can be used to heat and cool water and hoop house interiors.  Hoop houses can be low rise, ie vertical and only the height of the crops. They can unclip in sections from the walls to give access to the crops. The crops will be living off waste heat from the building and giving back the energy as food grown in aquaponics.  The green walls will also help to stop heat from escaping or entering the building in excessive amounts.  Urban farming in this way will also contribute to the total energy economy of a building.

runner bean

Climbing runner bean

In this way, the thick layer of coir matting and vegetation would also help insulate the inside of the building, and balcony gardens could also be part of the system.  Shade could be provided for those walking beneath as well if needed.  Marginal housing estates with little level garden space could convert themselves to thriving community vertical aquaponic urban farms. Urban farming could rescue whole areas from inner city blight.

Whole city districts might eventually be mostly covered by a layer of edible food trellis gardens apart from near the street level. Because food would be produced locally for local consumption using this method of urban farming, the costs passed on to the customer to pay for food transportation from distant farms would be eliminated.  Urban farming farms the food right next to the food consumer, and the consumer of this food does not have to pay high food prices with the cost of importing food included in the price.

This would completely change the character of cities and provide jobs maintaining the locally grown food supply for people who at present may not even be employed, with training and on the spot apprenticeships in vertical farming freely available to local people.

Aquaponics is a very flexible technology that can be adapted to all sorts of sites, as long as the biological balance between fish and plants in the system is correctly maintained.  Plant growth in aquaponics is usually much faster than in soil, so that maximum advantage can be taken of all the space under aquaponic crops.  Plant spacing is usually less as well, since plants are fed direct to the roots and do not have to stretch out root mass to find nourishment.  With some crops such as basil, it is possible to grow twice as much twice as fast, and the yields go on all year without seasonal rests.

red tilapia fish

Red Tilapia ready for sale

As far as species of fish in aquaponics are concerned for this kind of scheme, it really depends on whether your building has enough waste heat available for maintaining tropical species, or not. Tropical species of edible fish such as tilapia require constant water temperatures of 20-30 degrees C.  Trout and carp varieties, including ornamental koi carp, thrive best between 10-20 degrees C.

Tilapia grows from fish fry to plate size in 6-7 months, whereas most other species of fish take two years to reach a decent size. If your fish are also going to play an ornamental role and be visible to the public, this may also be a consideration when choosing a species to raise on your roof and/or in your basement. Of course, some species of tilapia such as Mozambique or red tilapia are ornamental cichlids as well as edible culinary fish. Tilapia species are robust and do well in aquaponics. I would recommend them at least to start with, as they are a bit more human error tolerant than say, trout and are less likely to die in protest if you make a few mistakes.

University of the Virgin Islands aquaponic system fish rearing tanks

University of the Virgin Islands aquaponic system fish rearing tanks

The aquaponics green wall possibilities are endless. It’s really up to you.

Jun 10

Aquaponics For Schools

lettuce seedlings in the UVI aquaponics system

Lettuce seedlings in the UVI aquaponics floating raft system.

University of the Virgin Islands commercial tilapia aquaponics system

University of the Virgin Islands commercial tilapia aquaponics system

To any ambitious biology or business teacher, a small commercial aquaponic farm is a priceless gift.  In any large flat roofed school building, you can have one on the roof and the students can run it as part of their classes, since it is automated largely.  But keeping an eye on the aquaponic organic food factory on the roof will teach them more about real biology, farming and agribusiness than any number of textbooks.

It may also provide the school with a much needed source of income in these interesting times.

But what is aquaponics?  Aquaponics is intensive fish farming in tanks married to intensive vegetable farming in tanks.  So you should know all about fish and plant biology as it applied to intensive aquaculture and hydroponics. This gives your students first-hand experience of looking after a natural ecosystem in an artificial container.  You also should know how to keep the water quality good enough to suit the plants and the fish. Chlorinated water cannot be used, since the disinfectant in the water kills the bacteria that make the fish waste into plant food, see the diagram below.

aquaponics flowchart

Aquaponics system biology flowchart

Fish excrete ammonia. Nitrifying bacteria in the filter part of the aquaponic system convert the ammonia to nitrates.  The nitrates are absorbed by the plants, and the plants grow really fast. This makes the water clean. The water is pumped back to the fish to be used again.

In aquaponics, only 1.5% of the water is lost in a properly designed and run aquaponics system. So it is very good for saving water on the farm. In aquaponics, plants can grow up to twice as fast at half the usual spacing. So you get up to twice as many plants, twice as fast, compared to farming in soil. But this can only be done if you have the right aquaponics system and the right training. As with any business, proper management is very important.

You will also need to know how to run and clean water pumps, air blowers, and alternative energy sources such as wind and solar generators.  You need a cheap source of electricity to run the machinery of your automated aquaponic food factory on the roof.

YOU DO NOT NEED SOIL IN AQUAPONICS. You only need water. And you do not waste any water.

Because you do not need soil, only tanks of water, you can do aquaponic farming anywhere, like on the school roof, as long as you have electricity and somewhere to put the tanks, the pumps, the air blowers, and the plumbing.

In the tropics, you do not need a permanent greenhouse, though in places like Hong Kong where the temperature goes down a lot in winter, you will need temporary plastic hoop houses to cover your aquaponic systems and also to protect them from typhoons. These have to be quite strong to keep the wind and rain off the system. For example, lettuces do not do well in temperatures below 10 degrees centigrade and above 20 degrees centigrade they start to die.

Pictured below is a gravity feed version of a small aquaponic system. You would need something larger than this to make the farm economically viable, but this give you a basic idea of what can be done with recycled materials and a tank or three.

Usually the first fish you use to make the fertilizer for your plants is the tilapia fish from the Nile originally. It is one of the most commonly farmed fish in the world. It is a tropical fish and does not stay alive in water below 19 degrees centigrade or above 30 degrees centigrade. You will need someone on your team who has kept tropical fish before and knows how to look after them!  If you live in a cold climate you will need to have some equipment to heat the water to the proper temperature and keep it that way.

Tilapia fish

Tilapia fish

gravity feed aquaponics system

Gravity feed aquaponics system

No fertilizers or pesticides can be used in an aquaponics system. They kill the fish! Instead, the fish water contains the nutrients that the plants need, and the pests can be controlled using biological methods.

Biological pest control methods include using friendly insects such as lady bugs to eat up all your aphids, also called greenfly.  There are also parasitic wasps and lacewings which also eat other pests as well. You can buy these online and they come in suspended animation in little blister packs. You spread them out with a camel hair paint brush so as not to damage them, and lift them onto the areas where the bad insects are eating your crops. That’s it!

Another way to get rid of pests such as caterpillars is to use a bacterium called bacillus thuringensis. This comes as a white powder which you spray on. It makes the caterpillars sick so they die, but is harmless to fish and people.

Here are some aphids and the ladybugs that like to eat them:

Aphids

Aphids eating a plant

 

Ladybugs

Ladybugs, ladybirds

You can also use harmless fats and oils to drown the insects that are eating your plants. But no insecticides or pesticides. They really do kill the fish, even if they are labelled ‘organic’!! You can be sure that none of the children will get poisoned by aquaponics for schools.

There are no weeds in aquaponic farming systems, so you do not need to use herbicide. So aquaponics for schools is not a toxic or dangerous activity.

There is no digging in aquaponics, and you can put the grow beds and raceways for the floating rafts up on tables and stands, so even people with bad backs can and do farm with aquaponic systems.

You can do all the work you need to do, including regular testing of the water to make sure the pH and other factors are correct, in a few hours a day. Your aquaponic systems are low tech mechanical systems with fish and plants growing in them. You have to make sure the fish and the plants have the best growing conditions. This sometimes means adding garden lime or potash to the water in tiny measured quantities to make sure that the water stays at a pH of around 7.0, or neutral.  This is something to do for your biochemistry classes. Looking at the kH and hardness of your water supply and other features of water quality analysis will give them lots of practical experience of how classroom work applies in the real commercial world of fish farming and modern recirculating aquaculture.

But before you go ahead and construct your own school aquaponics system, you need to look at all the business side of aquaponic farming in your area and do a business plan. If you cannot sell your fish and vegetables, you should not grow them!  Aquaponic systems can produce up to four times as much food for the space used, compared to conventional soil farming.  1/16 of a hectare of rooftop space can produce around 5 metric tons of fish and up to double that of vegetable plants a year. That is a lot of food to not be able to sell locally!  Schools that have their own aquaponic systems need to be sure that they are not going to have a lot of food that is simply rotting on the roof.  This is also very intensive fish and vegetable farming.

Market research is the first thing you do when you want to start a business, and aquaponic farming is a business. Aquaponic systems are very efficient food factories if properly managed and operated. This is something really interesting to do for your business class as a project. From your market research in local shops, markets and restaurants you can work out how much food you need to grow to cover the expense of constructing and operating a commercial aquaponic farm on the roof of your school. So then you can work out if there is enough room on your school roof for a big enough farm to cover your costs and perhaps make a bit of a profit. Aquaponics for schools is not aquaponics for fools!

If you are considering this kind of small commercial aquaponic intensive fish and vegetable farm on your school roof, please get in touch with us here

Call me! - Charlotte Appleton: Offline

» Get Skype, call free! and we can help you set this up correctly over Skype for a reasonable fee. If your farm is very big, it might be worth your while for a consultant to come and oversee the installation of your farm and the first few months of the business.  Aquaponics for schools can become aquaponics for whole communities.  If you get the whole community involved in their intensive fish and vegetable farm on your school roof, the sky is the limit!

Aquaponics Global Anthology 1 is available for instant download and to print out here: [paiddownloads id=”1″]

Jun 10

Aquaponics, Arcology, And Sustainable Development.

Aquaponics, correctly constructed and managed, is an essential part of sustainable development. Aquaponics is intensive fish farming in tanks married to hydroponics in tanks.  The reason that this has to be in tanks, not ponds, is that the tanks and associated plumbing and pumps allow much more intensive fish and plant production with close scientific water quality control. Also the water usage of an aquaponics system can be closely monitored and controlled to achieve water exchange rates of only 1.5%.  The water exchange rate is the water that has to replaced in the system when it is filled and pumping.  This compares favourably with water usage in conventional farming where the water exchange rate in an irrigated field is close to 100%.

floating raft aquaponics system

Simplified diagram, floating raft aquaponics system.

Water loss is minimal in aquaponics, which is a recirculating aquaculture system for both fish AND commercial crops. Food yeilds per hectare can be up to four times that of conventional farming, using far less expensive inputs, with proper trained and experienced management. Little ecological footprint is involved and pollution is not generated, since all nitrates are removed by the plants in the rafts, and the water recirculated to the fish in a clean reusable condition.

Aquaponics is now leading the way in successful urban farming enterprises in the United States such as Sweetwater Organics and Growing Power in Milwaukee, Wisconsin and Greater Growth in Knoxville, Tennessee.

As part of an arcology,aquaponics becomes a way of sustainably feeding thousands of people as a designed-in feature of the vertical self-sustaining city of the future.  Water is lighter than wet soil, which means that the floating raft aquaponics system as pictured above is suitable for including in buildings without so many of the crushing weight load problems associated with raised bed soil gardens. These urban farms can also yield over a million pounds of food on 1.5 hectares, as with the documented Growing Power urban aquaponic and sustainable farm in the city of Milwaukee. A picture of the floating raft system at the University of the Virgin Islands commercial aquaponic farm is included below.

Lettuce crop in floating raft aquaponics system

Lettuce crop in floating raft aquaponics system, UVI.

In the sustainable development of the city of the future, food security remains an urgent issue. Cities need to be unhooked from addicition to oil and gas, and the arcology requires no cars, as aquaponics requires no fertilizer or expensive pesticides and herbicides. The fish and pumps do most of the work!  As a plumbing system that sustainably produces food, aquaponics can easily be included in the modern arcology. This makes the sustainable development of a city that produces its own food with few inputs from outside very easy.

The best-known proponent of arcology urban design is the designer of Arcosanti, an arcology being built in Arizona, by the famous architect, Paolo Soleri.  He has developed and personally applied many of the design principles of the modern arcology. Another of his arcology designs is pictured below. There is easily space inside for a few large scale commercial aquaponics food factories and urban farms.

arcology soleri

One of the arcologies designed by Paolo Soleri

arcology

Model of an arcology with built in farm on roof.

The tank systems for the hydroponics and the fish farm can be built in to the design for the water and waste management systems for the arcology. As part of the atria inside the city, they can also be modules in the ornamental indoor park area features, with all of the plants both ornamental and edible, as a pick as you go salad bar for the population, who also maintain the public aquaponic farms with their floating raft beds of vegetables and associated intensive fish rearing tanks, on the various levels of the building.  Anaerobic digesters and wicking beds complete the picture, digesting organic waste and circulating the waste water from that as irrigation water for wicking beds that are used to grow root vegetables such as potatoes and carrots, that do not do well in floating raft systems.

A diagram of a wicking bed with its piping for the flowing waste water from the anaerobic digester is below.  It uses waste water from the anaerobic digesters.  It also uses digested solids that have been worm composted subsequently as the growing medium, thus returning organic waste at this last stage of processing to the state of edible food.  These design principles all hinge on recycling everything in the city through long cycles that safely transform organic waste back into food, water, and usable fuel.

wicking bed

Wicking bed-irrigation from below

Anaerobic digester power plants are also  a way of recycling water from waste management systems (such as sewage collection pipes). It is important to realize that all the organic waste, whether human or animal, fish or fowl, and all the vegetable and food waste, represent proper fuel for the anaerobic digester systems that produce methane gas that can be used to fuel boilers for hot water, heating, and steam generation for electricity producing turbines. This means that the aquaponic farm is a part of a sustainable development of a city which uses its own waste organic matter to generate both food and energy. Aquaponics is a very important technology in environmental engineering.

Waste solids from the anaerobic digester power plant are safe to use since they have been ‘cooked’ by the heat generated by the digestion process.  These solids can be further digested by using the worm composting method in large compost bins, and then used as the growing medium in the wicking beds, see the diagram opposite.  Many root vegetables, which have  a high nitrate fertilizer requirement, simply thrive in worm compost of this high quality. No digging is required in wicking beds if the upper portions are made of easily removable narrow gauge galvanized chicken wire or similar tacked to supporting posts with removable ties.

All of these technologies can basically be put on castors with wheels, and used like furniture in ‘food factory chambers’ in an arcology. Alternatively, the tanks and beds can be plumbed into the design at the outset, with all the factors calculated so that they meet the nutritional needs of the tens of thousands of people. Urban aquaponic farms and aquaponic farm parks will be a normal part of the pedestrianized environments of the near future’s new arcology urban neighbourhoods. Environmental engineering is very important in arcology design.

In an arcology, everything you need is in your part of the urban vertical stack, only within 20 minutes’ walk of where you live. There is no urban sprawl, the city extends upwards, if you need to go up a level, you walk up stairs or take the lift.  You do not need a car. The urban design has done away with the need for extensive road networks. Your neighbourhood is also your job, you participate in its maintenance and grow food with your community in your own area of the building, in a farm that is also a water pumping machine.

Light for the atria is brought into the building via lightwells with reflecting mirrors.  Low-energy restricted wavelength grow lights can be used on crops to increase the day length and speed of growth, fuelled by electricity which is made from organic waste from the city, its farms and restaurants. Solar collectors and wind-powered generators on the outside of the building also contribute to meeting the energy needs of the city’s inhabitants.  A city a thousand feet tall generates a lot of wind.

We at Aquaponics Global Ltd are available to assist in building the commercial aquaponic farm sections of any such civil engineering and architectural design and construction contracts.

anaerobic digester

Anaerobic digester methane tank, upper portion

 

Aquaponics Global Anthology 1 is available for instant download and to print out here: [paiddownloads id=”1″]

Mar 31

Weighing Up A Vegetable Garden On The Roof.

If you are considering building a vegetable garden on the roof, you will first have to consider the structural integrity of the building.

Flat rooves are not usually designed to carry a lot of weight, apart from the roofing materials.  If you are going to build a vegetable garden on your flat roof, how much do you think all the materials for it will weigh?

The load bearing capacity of your roof (how much weight it can safely bear without collapsing) must be taken into consideration.  Is your flat roof strong enough to carry the weight of your vegetable garden? Will you have to add strenghtening beams to it before you can start building your grow beds and so on?  How much will the soil that you are going to use weigh?

Wet soil, the kind of soil flowers and vegetables grow in, weighs a lot more than dry dust or compost as it comes in the bags.  Wet soil actually weighs more than water on its own.

To reduce the weight of your vegetable garden, as well as eliminating a lot of the maintenance work and expense involved, you should consider building a deep water culture aquaponics system, instead of using soil beds to grow your vegetables in your rooftop vegetable garden.

Aquaponics is the low-tech, but very scientific technique of growing plants in nothing more than fish water.  It does not use soil.  So you can significantly cut down the weight of the grow beds by replacing them with hydroponic deep water tanks of around 2 feet in depth.

These do not have to look ugly, and can conform to the space you have got up there.

However, you will also have to include an equal volume of fish tanks, since in aquaponics you grow fish and vegetables together in the same recirculating aquaculture system.  No fish, no fish water.

Whether you grow edible fish to eat, or just ornamental fish such as koi carp is entirely up to you.  But you need at least 250 gallons of fish tanks to 250 gallons of hydroponic tanks.  That is 500 US gallons of water.

500 US gallons of water weigh in at exactly 4,172.63 POUNDS.  However, the equivalent volume of soil will weigh more.  Soil, depending on moisture content, weighs in the neighborhood of 75 to 100 pounds per cubic foot, so assume maximum moisture, and you can immediately estimate how much more this will weigh than water. 500 US gallons is 66.84 cubic feet.  Multiply that by 100, and you get 6684 pounds.  That is 2511,37 pounds MORE than that same volume of water weighs.

So your aquaponic system will weigh a lot less than just the same area under soil beds.  This alone makes it more suitable for rooftop vegetable garden construction.

Also, an aquaponic system will grow you up to 40% more food, conservatively speaking, than your soil garden.  This is because you can grow your plants at up to half the spacing between them that you can in soil.  They also grow up to twice as fast in fish water, without any loss of taste or plant health.

So you get more plants, quicker, in aquaponics. Fish water just happens to be miracle grow organic fertilizer.

Of course, as they get big enough, if you are rearing edible fish, you get fish to eat or sell off.  If you are growing koi, you get valuable large koi to keep as pets or sell on to other koi carp enthusiasts.  Aquaponics gives you two products, fish and vegetables, from the same amount of space that a soil vegetable garden would only give you one, vegetables.

To justify the expense of constructing a rooftop vegetable garden, especially if it is a commercial one, you need to maximize the productivity of the space.  This is especially true in urban settings where high mortgages and rents come into the costs of your vegetable garden rooftop space.  Aquaponic systems are far more productive for the space occupied, with less hassle and expensive inputs such as labor and fertilizer.

You don’t have to buy any fertilizer with aquaponics.  The fish provide all the fertilizer you will ever need.

You aquaponic system is also largely automated.  With a normal raised bed rooftop vegetable garden, you have all the normal weeding, watering, and bending over to do.  This is not necessary at all with aquaponic systems. There is no weeding, watering or back breaking work to do.  The crops lift out on their floating rafts onto a trestle table for harvesting purposes.  Weeds cannot grow on polystyrene rafts.  The fish and pumps do the fertilizing and irrigation for you, automatically.  Friendly insects do the biological pest control as they hunt down the greenfly, etc.

You may, however, need to build a greenhouse over your rooftop vegetable garden in aquaponic systems.  This is because the best, most productive aquaponic systems can only produce crops and fish year-round in temperate climates if they have some protection from the weather, especially in winter.  Greenhouse conditions also give you more control over your biological pest control measures, and make it more pleasant to work there in bad weather.

By controlling the climate in a greenhouse, you can ensure that your rooftop vegetable garden in your aquaponic systems can reliably perform all year round, and supply your family and/or local community with fresh food grown locally.

This ensures the food security of your loved ones and neighbours, which is currently threatened by climate change and the unstable world economy.

Because you can grow fish as well as vegetables on your local flat rooftop, (providing the building is strong enough to carry the weight, as above), you are bypassing a lot of costly food delivery processes, such as the cost of transporting your food halfway round the world to the store.  This means that you can grow food more cheaply locally than imported food.

One of the ways to reduce rooftop vegetable gardening costs is to use recycled energy from the building to heat your greenhouse and water.  Heat exchangers can be fitted to take waste heat from heating and cooling systems and transfer it to your greenhouse air and water systems, such as your aquaponic systems.

There are many ways to make a rooftop aquaponic vegetable garden energy efficient without breaking the bank.  Solar greenhouse designs can be downloaded from the web.  Wind turbines and solar panels can be installed along with the right kind of storage batteries, that will save you a lot of electric bills in the long term.  The batteries mean you can run pumps and heaters at night as well.

Insulating your floors and tanks can also save energy.

The list of improvements and features you can build into a rooftop greenhouse is pretty long, and many of them actually can be constructed using recycled materials from the trash.

Did you know that one of the most advanced insulated greenhouse designs uses bubble wrap for the greenhouse walls?

When did you last see a skip full of discarded bubble wrap? Or wood from old forms for concrete building moulds?

You see what I mean.

Perhaps it is worth getting that flat roof to which you have access properly surveyed for weight loading?

Aquaponics Global Anthology 1 is available for instant download and to print out here: [paiddownloads id=”1″]