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List of automation needed for a container held aquaponics system:

All readings, data logging, and switching ON/OFF must be available for review/control via a webpage browser, with logging.

Some ideas how it looks like are visible here:

1) This senior citizen runs aquaponics with automation...

2) And younger man, self-made automation:

For each Aquaponics System:

1. pH meter in the water.

2. DO /Dissolved oxygen/ meter (in the fish tank) - low reading means something is rotting - dead fish, plant or similar. (and will raise the stink, and kill other stuff in the tank.)

3. Temperature - of the air and of the water in each of the tanks. (This will help track the biological processes.)

4. Time for each cycle in each Grow Bed. (How would we measure this? PGG)

5. Is the water pump running - reading to the voltage and amperage of the pump(s).

6. Speed of the water /if the water is moving, then pump is running and nothing is clogged.

7. Speed in the air /the air fans are running, and everything above said for the water pump - voltage and amperage readings for air fans.

8. light availability for plants (For natural lighting and to determine if the grow lights are operating correctly.)

9. Optical detection in the air conduits between modules to check for bee or other activity.

10. CO2 levels in air and water.

8. Luminosity in the container - are all the lamp emitting light, or some of them are burned out...

9. Relative humidity in the air.

10. Automated feeders for the fish. There is a research /for pity, in Bulgarian/ that automated feeding makes fish growth faster, and this leads to economy in regards to the food used per a kilogram of fish (1.5 kg pellets per 1 kg of fish weight increasement)

Hydroponics (and lighting) subsystem


1) By no means this is not a scientific work, even if many theoretical issues might be mentioned. The main task is to provide reasonable presumptions of building an aquaponic system, so the text below is just a guiding text. First thing is to run the system (with many redundancies and engineering suprluses), and only then to optimize it.

2) The initial contributor is Misho /Mihail Mateev/, who is not native English, so various spelling, syntax, word-order and other types of errors are expected.

3) The text is as laconic as possible, because many things are to be said and focus must be kept onto the goal - making an aquaponic system, not explaining theoretical matters.

Initial conditions and specifications:

Stage One: Aquaponics System, no limitations Stage Two: Aqiaponics System, 4 by 10 meters, cylindrical shell with R=4m, L=10m, sector of 1 meter is cut off. Stage Three: Aquaponics System, 4 by 20 meters, self-sufficient, subject to additional requirements.

Additional Requirements 1) Self-sufficiency 2) Bee hive at the final stage 3) Some equipment into the floor or under the floor is allowed.

Stage 1.

Aquaponics System constists of several subsystems, the major ones of which are hydroponics subsystem and fish subsystem. Additional there are several smaller subsystems, which serve previously mentioned ones, namely, energy subsystem, sensor subsystem, filter subsystem, insect subsystem, air conditioning subsystem, fish food production, seed production, fishling production, seedling production subsystems, etc. Each one of them should be examined in this document.

The style of this paper should be as much informative, fact-based, experience based, theory explained.

Frequently mentioned sources shall be placed at the end of the paper, one-time mentioned facts are quoted underline.

Hydroponics subsystem

There are several types of hydroponics subsystems.

1) Media based (Grow Beds) 2) Deep Water Culture (DWC), also called Floating Raft (FR) 3) Nutrient Film Technique (NFT)

Advantages and disadvantages on each one of them:

(to be added)

My choice is NFT system, combined with Grow Bed as bio-filter (as first filter of a few more).

Hydroponic Subsystem Design

Paul Graham - Project Director at has given some specifications on the fish tank for Stage 1, which follows:

Aquarium with dimension of 4 by 3 by 2 steps. Converted to Metric system, these dimensions are roughly 1200 mm by 900 mm by 600 mm /600 mm is height/.

If the water is 100 mm below the edge, then dimensions are 1200 by 900 by 500 mm.

Based on Aquaponics Secrets [2] 1200 plate-sized fish support 5000 NFT lettuces. This means that 1 fish supports approximately 4,2 plants.

Based on highest possible density for grown fish in Aquaponics Made Easy [1], which is 1 fish per 10 liters, first we need to estimate the water volume of the aquarium (also called here Fish Tank (abbreviation: FT)) in order to see how many fish we can have.

The volume of parallelepiped aquarium is most easy calculated, if any dimension is converted to decimeters (a decimeter is one-tenth of a meter), and then they are multiplied. The product is the volume in liters.

So: 1200 mm are 12 dm, 900 mm are 9 dm, 500 mm are 5 dm.

Therefore the volume V of the aquarium is V=12*9*5=540 dm3.

So the count of fish is the quotient of V divided by fish specific volume, in this case, 10 liters, so we have

N(fish)=V(FT)/V(fish) = 540/10 = 54.

So the number of plate-size fish is 54.

For the sake of calculations we may accept the count of fish as 50.

50 fish can support 210 plants (50 fish * 4.2 plants/fish = 210 plants)

The particular conception of proposed hydroponics subsystem is based on the video in Youtube [5].

Typical LED Spectrum:

LED spectrum of LED tube light

Sunlight peaks in the blue spectrum at 475 nanometers (nm). This is a shorter wavelength than red light and is used by both plants and algae. As light passes through water the intensity decreases. The shorter wavelength blue light penetrates water better and more quickly than red, which is slower and absorbed more quickly. Chlorophyll, the photosynthetic pigment used by plants traps blue and red light but is more efficient with red light at 650 – 675nm. Blue is used at the same rate as red because it is more available for reasons mentioned above.

For green plants the lighting peaks that are most important:

Chlorophyll-a: 430nm/662nm

Chlorophyll-b: 453nm/642nm

Carotenoids: 449nm/475nm

Red pigmented plants use more light in the blue area of the spectrum.

Peaks in wavelength, most desirable for plants

Typical Cool White LED Response, compared to human eye response:

Typical Cool White LED Response, compared to human eye response.

Warm White spectrum compared to Cool White spectrum (LED):

Warm White vs Cool White.

Emission spectrum of a phophor-based white LED manufactured by Nichia Corporation (Anan, Tokushima, Japan):

Emission spectrum of a phophor-based white LED

Spectrum of sunlight reaching the Earth compared to chlorofyll spectrum:

Spectrum of sunlight reaching the Earth compared to chlorofyll (and other compounds) spectrums

Photosynthetic Action Spectrum:

Photosynthetic Action Spectrum

All fluorescent and MH bulbs have a discrete spectrum, whereas sunlight has a continuous spectrum. Discrete spectrum is a result of using a discharge in mercury (and other metal) vapors, with several peaks at different wavelengths, mostly in the ultraviolet range. Phosphors on the bulb convert this radiation into narrow bands of visible light.

A discrete spectrum (below) vs. continuous spectrum (above)

All fluorescent and MH bulbs also are very fragile and short-lived. So LED lights, being solid, long-lived, and with continuous spectrum tend to be superior over other current solutions for lighting, especially for extraterrestrial applications.

PAR, MH and LED spectra compared

PAR, MH and LED spectra compared

Waste of energy in HID spectrum

Great share of HID light is wasted, as it is not absorbed by the plants

LED spectrum of TO46 with exact positions of wavelengths:

LED spectrum of TO46 with exact positions of wavelengths

LED spectrum of TO46 with exact positions of wavelengths, overimposed on peaks in wavelength, most desirable for plants.

LED spectrum , overimposed on peaks in wavelength, most desirable for plants.


Candela: The candela (/kænˈdɛlə/ or /kænˈdiːlə/; symbol: cd) is the SI base unit of luminous intensity; that is, power emitted by a light source in a particular direction, weighted by the luminosity function (a standardized model of the sensitivity of the human eye to different wavelengths, also known as the luminous efficiency function[4][5]). A common candle emits light with a luminous intensity of roughly one candela. If emission in some directions is blocked by an opaque barrier, the emission would still be approximately one candela in the directions that are not obscured.


Also: Candela is unit for "luminous flux per unit solid angle"


Candlepower: Candlepower (abbreviated as cp) is an obsolete unit expressing luminous intensity, equal to 0.981 candela. It expresses levels of light intensity in terms of the light emitted by a candle of specific size and constituents. In modern usage candlepower equates directly to the unit known as the candela.



The lumen (symbol: lm) is the SI derived unit of luminous flux, a measure of the total "amount" of visible light emitted by a source. Luminous flux differs from power (radiant flux) in that luminous flux measurements reflect the varying sensitivity of the human eye to different wavelengths of light, while radiant flux measurements indicate the total power of all electromagnetic waves emitted, independent of the eye's ability to perceive it. A lux is one lumen per square meter.

The lumen is defined in relation to the candela as 1 lm = 1 cd·sr

A full sphere has a solid angle of 4·π steradians, so a light source that uniformly radiates one candela in all directions has a total luminous flux of 1 cd·4π sr = 4π cd·sr ≈ 12.57 lumens.


Practical definition of Lumen: "Luminous Flux (Lm): The luminous flux is a measure of the total light output from a source. For example, a 1 candela light source will product 1 lumen per square meter at the distance of 1 meter."


Lux: The lux (symbol: lx) is the SI unit of illuminance and luminous emittance, measuring luminous flux per unit area.[1] It is equal to one lumen per square metre. In photometry, this is used as a measure of the intensity, as perceived by the human eye, of light that hits or passes through a surface. It is analogous to the radiometric unit watts per square metre, but with the power at each wavelength weighted according to the luminosity function, a standardized model of human visual brightness perception. (Source:


The steradian (symbol: sr) or squared radian is the SI unit of solid angle. It is used in three-dimensional space, and functions analogously to the manner in which the radian quantifies planar angles. The name is derived from the Greek stereos for "solid" and the Latin radius for "ray, beam".

The steradian, like the radian, is dimensionless, essentially because a solid angle is the ratio between the area subtended and the square of its distance from the vertex: both the numerator and denominator of this ratio have dimension length squared. It is useful, however, to distinguish between dimensionless quantities of different nature, so in practice the symbol "sr" is used to indicate a solid angle. For example, radiant intensity can be measured in watts per steradian (W·sr−1). The steradian was formerly an SI supplementary unit, but this category was abolished from the SI in 1995 and the steradian is now considered an SI derived unit.

Definition: A steradian can be defined as the solid angle subtended at the center of a unit sphere by a unit area on its surface. For a general sphere of radius r, any portion of its surface with area A = r2 subtends one steradian.

Because the surface area of a sphere is 4πr2, the definition implies that a sphere measures 4π ≈ 12.56637 steradians. By the same argument, the maximum solid angle that can be subtended at any point is 4π sr.


Design with Cool White LED Tubes

This is to be removed or to remain as single section once the multi-color LED is implemented.

This section is written for two purposes:

1) To have a complete design even with something as not so effective as white light, instead of reddish/bluish LEDs.

2) If the design proves itself worthy, it may be used as an non-expensive option for aquaponic lighting system for students, poor people, etc.

Lighting design has is using the Youtube video from 5) DIY Indoor Vertical Hydroponics System. It is 80 slots in 2" (50mm) PVC tubes, the centers of the slots are separated by 150mm. In the comment of last video ( the user mentions the fluorescent lights are 4 tubes by 32W, 120cm long; 16h of lighting, 8h of darkness. In the updates has complained the plants, which were not under the direct light of the fluorescent tubes were not growing so fast. The pump is 400 GPH (1500 Liters per hour). The water lines are 6mm in diameter.


For sources of images, if not mentioned expressively, links are provided into description of the images. One has to click on it to see it.

1) Aquaponics Made Easy:

2) Aquaponics Secrets:



5) DIY Indoor Vertical Hydroponics System : (playlist is available here:

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