Difference between Hydroponics – Aquaponics

What is the difference between Hydroponic and Aquaponic Systems?

In discussing the differences between these 2 systems it is important to note that BOTH do have some similarities (in that a water solution is required) and the great benefit is – FRESH HOME PRODUCE without the use of added chemicals and sprays.

So BOTH will provide you and your family with HEALTHY PRODUCE for you to eat.

Hopefully you will note that we are not pushing the agenda of either system, however, in my own case because of space considerations I started with hydroponics and had wonderful results.

Building upon that experience, I was thrilled when I discovered Aquaponics and would certainly encourage any beginner to go straight into Aquaponics if you have the opportunity as there is more scope for adventure and spectacular results – if you have the space.  Time needed to service both is similar.

BEFORE WE COMMENCE – it is important you know that BOTH use WATER to encourage plant growth.


How to use a Hydroponic System

Often the plants in a hydroponic system grow with their roots dangling into the water (grow bed), and certainly NOT in soil.  In many designs the plant is supported by the use of a growing medium which does little except to ensure the plant is able to grow toward to sky, however, as I write this statement I am reminder from experience that the growing medium also holds the water (and added nutrients) close to the root (for an additional drink whenever needed) as well as helps to prevent evaporation of the water.

This growing medium can take many form and is often perlite, vermiculite, gravel, sand, rockwool broken coconut husks, crushed apricot centers etc just to name a few and is almost always just some inert item that does not supply or have any nutrient value for the plant or system.

Nutrients are added to the water, which water (and added nutrients) are then circulated through the system so that the roots are wet enough to absorb the nutrients contained in the distributed water.

Thus you provide and personally supervise the pH level of your nutrient solution so that the plant are given exactly the food you wish the plants to receive and this also enable you to ensure NO CHEMICALS ARE ADDED which has the benefits of producing health food for you and your family.

Whilst you can provide a continual supply of nutrient/water solution to your plants it is also possible for you to provide this nutrient/water solution even as little as once a day (for about 30 minutes minimum) then let the solution drain away into a storage tank. Then either automatically by the use of an inexpensive timer or else manually raise or pump the solution down the system so that the plants get “a regular drink”.

It is even possible to design a manual system so you water either early in the morning or later at night, however, avoid daytime flooding/drinking if possible.  Hopefully you appreciate that you have a lot more flexibility with hydroponics over trying to grow using soils, including even organic soils.

Hydroponics permits the controlled use of fertilizers nutrients such as nitrogen, phosphorus and potassium which when obtained from a “real hydroponic supplier” will be able to provide the fertilizer in the correct proportions. Organic fertilizers can provide surprising results because some providers add a better mix that seem to be better assimilated by plants – I wish I knew their secrets.

It would appear that some providers go to the trouble of adding small quantities of trace elements such as boron, calcium, cobalt, copper, iron, magnesium, manganese, molybdenum, sulfur and zinc all of which are necessary in soil farming, as so the growth results and food quality can be spectacular.

A list of Trace Minerals (elements) in descending order of our bodies dependences / needs is as follows:-

Magnesium, Chloride, Potassium, Sulfate, Sodium, Boron, Bromide, Calcium, Carbonate, Silicon, Nitrogen, Selenium, Phosphorus, Iodine, Chromium, Iron, Manganese, Titanium, Rubidium, Cobalt, Copper, Antimony, Molybdenum, Strontium, Zinc, Nickel, Tungsten, Germanium, Scandium, Tin, Lanthanum, Yttrium, Silver, Gallium, Zirconium, Vanadium, Beryllium, Tellurium, Bismuth, Hafnium, Terbium, Europium, Gadolinium, Samarium, Cerium, Cesium, Gold, Dysprosium, Holmium, Lutetium, Erbium, Ytterbium, Neodymium, Praseodymium, Niobium, Tantalum, Thorium, Thallium, Rhenium, plus other rare minerals found in seawater.

It is important to remember that too much of one trace element can lead to an imbalance in others, and that  they need to be available to our intestines in ionic form in order to be properly absorbed by our bodies.

Be wary of adding anything to your hydroponic solutions because it is so easy to lose all your crop. Better to segregate part of your crop into a “test area” so you can test various alternative solution (if you so wish), however, remember the pH level is of critical importance to the success of your crop as pH does affect the absorption abilities of plants.

Compared to farming in soils (earth), hydroponic systems are more profitable because of higher growth and yields in crops.

Hydroponics are suitable for indoors, outdoors and commercial food production.

How to use a Aquaponic System

An Aquaponic Eco System is similar to a Hydroponic System except that Aquaponics is all about creating a NATURAL ECO SYSTEM so the use of introduced fertilizers, insecticides, pesticides and herbicides and similar is FORBIDDEN and in addition because there is a natural eco system with a renewable process in the case of Aquaponics, it is possible to add marine life such as fishes into the balanced watery solution without causing any distress to the marine life.

The marine life especially in the form of fishes create their natural “poop” nutrient dense waste which has a high content of ammonia which is then attacked by bacteria in the water solution to create natural nutrients (firstly into nitrites then into nitrates) which the plants (vegetables) use as their natural food source and hence they grow a variety of crops as an organic plant (no matter what type of plant they are) because no non-natural chemical or similar ingredient was use, hence they are truly ORGANIC.

So if you are thinking that Aquaponics is really Hydroponics with a few enhancement such as edible fish, you would get no argument except that the Eco System aspect is more enhanced.

Aquaponics is a true copy of nature where plant and marine life are integrated with the recycling of nutrients and water filtration (from plant roots) enable a sustainable food production model.

Uneaten fish foods and “poop” accumulate in the water to create effluent-rich waters, however, these become toxic to marine life when in high concentrations.  By the action of moving the water through-out the eco system (by pumping the water – usually using an electrical motor) these effluents are more readily available to the plant life who require these nutrients essential to their very growth.

Aquaponics is a renewable process and this type of organic farming can take many different forms and can be in a small indoor system, a medium size outdoor system or can be a large commercial system.  The plants can be permanently immersed in water by placing them on floating rafts or else they can be dipped, splashed or sprayed from time to time or may be even be flooded then drained frequently.

Providing some basic attention is devoted to the system you will find the eco system will self balance just as occurs naturally in nature. The most significant issues to monitor are the pH, temperature and oxygenation. By monitoring these items and ensuring the fish are kept healthy you will discover the eco system and the fish will take care of the plants (vegetables) and in turn the plants will ensure the water is kept healthy for the fish.

In summary

Both Hydroponics and Aquaponics are soils free methods for cultivating crops.

Aquaponics incorporates a hydroponic environment with aquaculture (by the addition of fish) such that there is a controlled environment that allows the creation of a sustainable balanced eco system that supports and benefits both marine life and crops (vegetables etc).

In Hydroponics you need to add nutrients regularly to the water. The nutrient rich water has inert mediums such as sand, gravel. perlite etc placed into the water to hold and stabilize the plants in place (so the plants do not fall over), as the plants easily absorb the nutrients and therefore grow faster and with a higher yield compare to growing in soil making this method very profitable.

Over time the water used in a Hydroponic system becomes so out of balance and toxic that the water becomes unusable and must be discarded and replaced (whereas this should not happen in Aquaponics).

Care must therefore be taken in disposing of this over-nourished waste water which can produce poisonous toxins otherwise you risk damaging aquatic animals, plant life, animals and humans.

Perhaps you have heard the word “aeroponics” – this is where the roots of the plants are sprayed with a Hydroponic mixture of nutrient water (rather than being immersed in a body of water). Both produce pleasing results and may be more suitable than Aquaponics in some situations, particularly when space is at a premium.

In Aquaponics the principal of Hydroponics apply except that NO NUTRIENTS ARE EVER ADDED. A connection is made to a larger body of water so as to enable the 2 connected systems to establish an eco system (balanced like in nature) to be created and maintained. Into this eco system fish are added so that the fish become larger and fat enough to be eaten by you and your family. You will need to add fish food (in limited small quantities) so that the fish will grow and “poop” into the water – but that is all that is ever added to the water.

Aquaponics uses the fish waste material by treating that waste with natural bacteria to create nutrients that are usable as nourishment for the plants (vegetable, shrubs, trees etc). So the waste (nitrites) is converted to plant food (nitrates).

The plants life in turn returns clean water suitable for marine life to exist in the eco system and so the whole cycle is repeated whilst ever a balance eco system is sustained.

Remember in Aquaponics you do need to watch the water pH level (acid / alkaline measurement), temperature and oxygenation. Over time evaporation of the water in your eco system will slowly evaporate and hence some additional water will need to be added.

When adding water be conscious of issues such as fluoridation (added to tap water by most Government supply sources) and so a settling tank is idea to allow such added chemicals to settle out of the main body of water you will use to “top-up” your eco system.

Ideally you will also use “filters” to assist in the controlled introduction of bacteria (discussed elsewhere on this site).


Both the Hydroponic and Aquaponics systems are exciting to experience and experiment with – because I believe that “innately” our spirit is meant to provide for ourselves in a rustic sort of way. Perhaps we were never meant to live in massive cities and hand over our food destinies to large agricultural-food corporations.

Certainly there is much to excite your soul when you experience plants growing (and even more exciting when you start to eat and enjoy the lovely fresh taste of non-chemical foods), however, the added bonus of experiencing LIVE ANIMALS in the form of fish in the Aquaponic eco system model is enthralling and captivating.

Knowing that Aquaponics provides fresh natural food in an identical way to Nature is very empowering and satisfying in so many ways.  You are encouraged to make a start because the cost is truly low and you are capable of personally completing all the construction work required.

Perhaps we should just mention in passing a minor issues you may wonder about:-

the words “Aquaculture” and “Aquaponics” are similar but do reflect 2 slightly different forms of farming – which both use fish.

In a typical Aquaculture system the waste water is not recycled – water is taken and pumped or sprayed “away from” the original fish tank “which is NOT CONNECTED” to the grow boxes used to hold the growing plants life.

In Aquaculture the water from the fish tank is transferred to the tank holding the plants (perhaps by pumping the water across – as neither are directly connected) whereas in Aquaponics the fish tank and the plant tanks are all (both) connected as one system so that a balanced eco system can be created and sustained.