James M. Ebeling, Ph.D.
Research Engineer
Aquaculture Systems Technologies, LLC
Michael B. Timmons, Ph.D.
Professor
Dept. of Bio. & Environ. Eng.
Cornell University
HYDROPONICS
•
•
•
RAFT
NFT
RECIPROCATING
2015 Engineering Design & Water Quality
HYDROPONICS
• FLOATING RAFT
• NFT
• MEDIA BED
• DRIP
2015 Greenhouse Crop Production & Engineering Design Short Course
Fish Culture Tank
“Anything that holds water”
2015 Greenhouse Crop Production
& Engineering Design Short
Course
Fish Culture
Tank
“Anything that holds water”
2015 Engineering Design & Water Quality
Fish Culture
Tank
2015 Greenhouse Crop Production & Engineering Design Short
Course
Fish Culture
Tank
2015 Greenhouse Crop Production & Engineering Design Short
Course
Fish Culture
Tank
!
2015 Greenhouse Crop Production & Engineering Design Short Course
Fish Culture
Tank
2015 Greenhouse Crop Production & Engineering Design Short Course
Fish Culture
Tank
2015 Greenhouse Crop Production & Engineering Design Short Course
Fish Culture
Tank
“Cornell type” Dual-Drain Culture Tanks”
"RULE OF THUMB"
Dual-Drain Design



Dia:Depth = 3:1 to 6:1
15 to 25% through center drain
75 to 85% through sidewall discharge
2015 Engineering Design & Water Quality
Fish Culture
Tank
HRT = Hydraulic Retention Time
Drain lines vs. Pumped Return Lines
"RULE OF THUMB"
Circulation




Fry/Fingerlings – 15 to 30 Min HRT
Growout – 30 to 45 min HRT
Broodstock – 60 min HRT
Purging – 1 to 2 Tank exhanges per day
Maximum Flow (gpm)
Pipe Dia
(inches)
Drain Line
(1 to 2 fps)
Pumped Return
(< 5 fps)
1/2
3/4
1
1.5
2
3
4
6
1
2
5
10
20
45
75
150
5
10
15
30
50
125
200
500
2015 Engineering Design & Water Quality
Fish Culture
Tank
Weight = function (length)3
3
inches
6
L
Wtlbs  CF 
10
Growth = function (Temperature)
Inches T  Tbase
Growth 

month TU base
"RULE OF THUMB"
Trout
Tilapia
Perch
Tbase
32
65
50
TUbase
28
15
25
Tmax
72
85
75
Weight vs Length
•
CFtrout
=
400
•
CFtilapia
=
760
•
CFperch
=
490
•
CFstriped bass =
720
2015 Engineering Design & Water Quality
Fish Culture
Tank
Fish Culture Density
Ddensity 
L
C density
"RULE OF THUMB"
Fish Culture Density (at harvest)
Ddensity
Density in kg/m3 (lbs/ft3)
L
Length of fish in cm (inches)
Cdensity
tilapia: 0.24 for L in cm (1.5 for L in inches)
trout: 0.32 (2.0)
perch: 0.40 (2.5)
hybrid striped bass: 0.45 (2.8)
2015 Engineering Design & Water Quality
• Swirl separators/
Radial Flow Clarifers
"RULE OF THUMB"
Radial FlowDesign
Surface-loading rate for the radial-flow settler 4.6 gpm/ft2 of settling area
2015 Engineering Design & Water Quality
75-90%
Suspended
Solids
• Screen
Sludge
filtration
• rotating microscreens
• horizontal screen
• vertical screen
• Pressurized bead filters
outlet
• Pressurized sand filters
P
• Bag filters
inlet
emergency drain
2015 Greenhouse Crop Production
& Engineering Design Short
Course
• Screen
filtration
• Pressurized bead filters
Propeller Washed Bead Filter
Bubble Washed
Bead Filter
"RULE OF THUMB"
Suspended Solids Capture Design
•
•
Bead Filter – 5 to 6 lbs of feed per flush per ft3 of media
Screen Filters – see manufacturer recommendations
2015 Engineering Design & Water Quality
• Foam Fractionation
• Protein Skimmers
Fine & Dissolved
Solids Removal
Sludge
"RULE OF THUMB"
Foam Fractionation
Tank Volume treated every 2 to 4 hours
2015 Greenhouse Crop Production & Engineering Design Short Course
75-90%
Suspended
Solids
Sludge
2015 Greenhouse Crop Production & Engineering Design Short Course
Solids Disposal
• Land application
By-Product
NOT a Waste Stream
• Aquaponics
• GeoTextile Bags
• Composting
2015 Engineering Design & Water Quality
75-90%
Suspended
Solids
Sludge
2015 Greenhouse Crop Production & Engineering Design Short
Course
75-90%
Suspended
Solids
Sludge
"RULE OF THUMB"
Suspended Solids Capture Design
Bead Filter – 5 to 6 lbs of feed per ft3 of
media
2015 Greenhouse Crop Production & Engineering Design Short Course
75-90%
Suspended
Solids
Sludge
2015 Greenhouse Crop Production & Engineering Design Short Course
Sludge
By-Product
NOT a Waste Stream
• GeoTextile Bags
• Land application
• Composting
• Aquaponics
2015 Greenhouse Crop Production & Engineering Design Short Course
Biofiltration / Nitrification
Ammonia Oxidizing Bacteria
2 NH4+ + OH - + 3 O2  2 H + + 2 NO2- + 4 H2O
Ammonia
Nitrite
Nitrite Oxidizing Bacteria
2 NO2 + 1 O2  2 NO3Nitrite
Nitrate
"RULE OF THUMB"
Nitrification of 1 g of ammonia-nitrogen
1 KG FEED  ABOUT 0.03 KG AMMONIA
• Yields – 5.93 g of carbon dixoide
• Consumes – 4.57 g of oxygen and 7.14 g alkalinity
2015 Engineering Design & Water Quality
Moving Bed Biofilter
Bead Bioclarifiers
"RULE OF THUMB"
MBBR Design
•
•
•
•
•
•
17.14 g TAN/ft3 /day curler media @ 25 to 30 Deg C
13.26 g TAN/ft3 /day @ 15 to 20 Deg C
10.14 g TAN/ft3 /day @ 5 to 10 Deg C
3 to 5 min HRT
50% fill factor – max 65%
Air flow: 0.125 scfm/ft3 of reactor
About 1 g TAN / m2 of media per day or
~ 500 to 1000 g per cubic meter per day
2015 Engineering Design & Water Quality
“RULE OF THUMB”
1 KG FEED  ABOUT 1 KG OXYGEN
2015 Engineering Design & Water Quality
2015 Engineering Design & Water Quality
Aeration
Air/Oxygen
Aeration Systems
Air Stones, Packed Towers
Oxygenation Systems
Micro-Diffusers, Speece Cones
"RULE OF THUMB"
2015 FEED
Greenhouse
Crop
Production
1 KG

0.65
TO 1.00 KG OF O2
& Engineering Design Short
Course
• Ozone
•
Disinfection
Ultraviolet radiation
"RULE OF THUMB"
UV
•
30 mW-sec/cm2
•
10-30 second contact
times
2015 Greenhouse Crop Production & Engineering Design Short
Course
Monitoring &
System Control
Continuous
Periodically
•
•
•
•
•
•
•
•
•
•
•
DO
Level
Flow
Temperature
Air pressure
pH
NH3
NO2
NO3
CO2
Alkalinity
Phone Dialer
It takes only one mistake to KILL
EVERYTHING IN YOU FACILITY!!!!
2015 Greenhouse Crop Production
& Engineering Design Short
Course
The most sophisticated
monitoring and alarm system
is an attentive human
operator!
MONITORING &
SYSTEM CONTROL
Water Level
Local audible alarms for
Low and High Water Level
Alarm Low
Water Level
High Water
Level
Low Water
Level
2015 Engineering Design & Water Quality
Loss of Oxygen
•
•
More fish are probably lost in
recirculation systems due to lack of
oxygen than to any other single cause!
(actually, draining the tank unintentionally
is the number one reason)
normally open, electrically
operated solenoid valve
A three tier emergency oxygen supply is
not an extravagance (Just ask NASA!)
2015 Engineering Design & Water Quality
Monitoring &
System Control
Sensaphone WEB600 Based Monitoring System
Sensor Inputs: 6 Universal Inputs
• Normally Closed/Normally Open Dry Contacts
• 2.8 and 10K Thermistors for Temperature
• 4-20 mA Current Loop for external sensors, pH,
EC, DO
Alarm Notification Methods:
E-mail, text messages
Web page
Eight alarm levels, 8 programmable user profiles
Data Logging: 32,000 samples (date and time
stamped) from every second to monthly
Monitoring &
System Control
2015 Greenhouse Crop Production & Engineering Design Short Course
2015 Greenhouse Crop Production & Engineering Design Short
Course
• Water Quality Lab
• Storage - Feed, Chemicals, Product
• Equipment Storage
• Staff Support
• Back-up Generator
• Quarantine Area
• Waste Disposal
2015 Greenhouse Crop Production
& Engineering Design Short
Course
48" top by 39" bottom diameter
x 25" depth with 20" of water
PolyTank PT-4825
2 ft x 2 ft
x 3 ft deep
Fiberglass Sump
Sequence Model 1000
3300SEQ21 SEQ
Sump
UV
Drain
To Raft System
BBF-4 cuft
BioClarifier
Airline
Backwash Drain
2015 Engineering Design & Water Quality
Unless You’re a Fish,
You Can’t Tell By Sticking Your Fin in the Water!
Critical Parameters
• dissolved oxygen
• temperature
• pH
• un-ionized ammonia
• nitrite
• nitrate
• carbon dioxide
• alkalinity
• solids
2015 Engineering Design &
Water Quality
• CO2 and dissolved oxygen concentrations
• pH versus ammonia-nitrogen concentration
• Temperature and growth rate and health
2015 Engineering Design & Water Quality
Too much is definitely better than too little!
Amount of water needed will depend on:
• species
• density
• management practices
• production technology
• degree of risk one is willing to accept
“Rule of Thumb”
100% water exchange of total system volume per
day (good operators will do 3 to 20% per day)
2015 Engineering Design & Water Quality
• Groundwater
• Surface Water
• Municipal Water Supplies
2015 Engineering Design & Water Quality
Advantages:
•
Constant Temperature
Disadvantages:
•
Dissolved H2S and CO2
• Low Dissolved Oxygen
• Supersaturation
• High Iron Concentration
2015 Engineering Design &
Water Quality
Advantages:
•
Available??
• None
Disadvantages:
•
High / Low Temperatures
• Disease!!!!
• Pollution!
• Too Many!
2015 Engineering Design &
Water Quality
Designed and treated to safeguard
the health of humans, not fish!
Advantages
• Availability
• Reliability
Disadvantage
• Chlorine
• Chloramines
• Fluorine
• Cost
2015 Engineering Design & Water Quality
Parameter
Concentration (mg/L)
Alkalinity (as CaCO3)
50-300
Ammonia (NH3-N unionized)
< 0.0125 (Salmonids)
Ammonia (TAN) Cool-water fish
< 1.0
Ammonia (TAN) Warm-water fish
< 3.0
Carbon Dioxide (CO2)
Tolerant Species (tilapia)
< 60
Sensitive Species (salmonids)
< 20
2015 Engineering Design & Water Quality
Parameter
Concentration (mg/L)
Hardness, Total (as CaCO3)
> 100
Iron (Fe)
< 0.15
Nitrogen (N2)
< 108% total gas pressure
< 103 % as nitrogen gas
Nitrite (NO2-N)
< 1 (0.1 in soft water )
Nitrate (NO3-N)
0 - 400 or higher
2015 Engineering Design & Water Quality
Parameter
Concentration (mg/L)
Oxygen Dissolved (DO)
>5
> 90 mm Hg partial pressure
Ozone (O3)
< 0.005
pH
6.5 - 8.5
Salinity
< 0.5 to 1 ppt (Osmotic Regulation)
Total dissolved solids (TDS)
< 400
Total suspended solids (TSS)
< 40
Total Gas Pressure
< 103 % (death at ~ 108%)
2015 Engineering Design & Water Quality
Critical Parameters
• Dissolved Oxygen
• Temperature
• Ammonia/Nitrite/Nitrate
• pH
Important Parameters
• Alkalinity/Hardness
• Salinity
• Carbon Dioxide
• Solids
2015 Engineering Design & Water Quality
Equilibrium Reaction - Ammonia
NH4+ + OH - 
Non-Toxic!
NH3 + H2O
Toxic!
Increase in pH
Increase in temperature
Note: NH4+-N + NH3-N  TAN
NH4--N  Ammonia - nitrogen
2015 Engineering Design & Water Quality
Percent unionized Ammonia-nitrogen
Temp.
10ºC
15ºC
20ºC
25ºC
30ºC
6.0
0.1
0.1
6.5
0.1
0.1
0.1
0.2
0.3
pH
7.0
0.2
0.3
0.4
0.6
0.8
7.5
0.6
0.9
1.2
1.8
2.5
8.0
1.8
2.7
3.8
5.4
7.5
9.0
15.7
21.5
28.4
36.3
44.6
2015 Engineering Design & Water Quality
Equilibrium Reaction – Nitrite
NO2- + H2O 
HNO2 + OH -
Decrease in pH
Note: NO2--N  Nitrite - nitrogen
(mitigated by adding salt (chlorides)
2015 Engineering Design & Water Quality
Equilibrium Reaction – Nitrate
NO3-N
Non-toxic (freshwater systems)
Can be Problem in saltwater systems
Note: NO3--N  Nitrate - nitrogen
2015 Engineering Design & Water Quality
pH value expresses the intensity
of the acidic or basic characteristic of water.
Seawater: 8.0- 8.5
Freshwater: 6.5 – 9.0
Hydroponic systems like pH ~ 5.8 …a challenge for
Aquaponics !
2015 Engineering Design & Water Quality
Alkalinity
(50 -150 mg/l as Ca CO3)
Formula
Common Name
Equivalent Weight
NaOH
sodium hydroxide
40
Na2CO3
sodium carbonate
53
NaHCO3
sodium bicarbonate
83
CaCO3
Calcium Carbonate
50
CaO
slaked lime
28
Ca(OH) 2
hydrated lime
37
2015 Engineering Design &
Water Quality
Alkalinity 100 mg/L
100
90
80
CO2, mg/L
70
60
50
40
30
20
10
0
6.50
7.00
7.50
8.00
8.50
pH
The relationship between pH,
alkalinity, and CO2 concentrations.
2015 Engineering Design & Water Quality
Classified as:
soft (0-75 mg/L
moderately hard (75 – 150 mg/L)
hard (150-300 mg/L)
very hard (> 300 mg/L)
Recommended range: 20 to 300 mg/L CaCO3
2015 Engineering Design & Water Quality
• Carbon dioxide is a highly soluble in water.
• Concentration in pure water: 0.54 mg/L at 20° C.
• Groundwater concentrations range from 0-100 mg/L.
Exposure to high carbon dioxide concentrations
reduces respiration efficiency
and decreases the tolerance
to low dissolved oxygen concentrations.
2015 Engineering Design & Water Quality
Three categories:
• settleable
• suspended
• fine or dissolved solids
“Rule of Thumb”
Solids produced by fish :
0.25 to 0.4 kg TSS for every
1 kg of feed fed
• upper limit: 25 mg TSS/L
• normal operation (species dependent)
• 10 mg/L for cold water species
• 20 – 30 mg/L for warm water species
2015 Engineering Design & Water Quality
Usually reported as parts per thousand, ppt.
Osmoregulation
“Rule of Thumb”
To reduce stress and reduce energy
required for osmoregulation,
freshwater aquaculture systems
are maintained at 2-3 ppt salinity.
2015 Engineering Design & Water Quality
Winkler Titration
DO Meters – polarographic
- galvanic
- optical
2015 Engineering Design & Water Quality
Dr. James M. Ebeling
18 years – Cornell University Short Course
HBOI Short Course
Dr. Michael B. Timmons
Cornell University Professor
2015 Engineering Design & Water Quality
For copy of presentation: JamesEbeling@aol.com
2015 Engineering Design & Water Quality
James M. Ebeling, Ph.D.
Michael B. Timmons Ph.D.
Research Engineer
Tucson. AZ
J.Thomas Clark Professor of
Entrepreneurship & Personal Enterprise
Cornell University
THE FISH!
“Closed Environmental Life
Support System for Fish and Plants”
OUT
Unit Operation
(Treatment Process)
IN
HYDROPONICS
•
•
•
RAFT
NFT
RECIPROCATING
2015 Greenhouse Crop Production & Engineering Design Short Course
Advantages of Aquaponics with RAS systems
• Dissolved nutrients recovered by plants
• Minmizes water exchange rate
• Secondary crop – improves profitability
Disadvantages of Aquaponics with RAS systems
• Large ratio of plants area to fish rearing area
• New set of skills –’Green Thumb’
• Limits treatment options for both plants and fish
2015 Greenhouse Crop Production & Engineering Design Short Course
Water Based Culture:
•
•
Floating Hydroponic Technique
(Raft Culture, Deep water Culture)
Nutrient Film Technique (NFT)
Media Based Culture:
•
•
•
•
Reciprocating Systems
(Ebb & Flow, Flood & Drain)
Dutch Bucket
Drip System – Rockwool Slabs
Air Based Culture:
•
•
Aeroponics
Vertical Gardens
2015 Greenhouse Crop Production & Engineering Design Short Course
Hydroponics – Raft System
Nelson & Pade, Inc.
Friendly Farm Hawaii.
Lettuce Factory, Ithaca, NY
Tanque Verde High School
2015 Greenhouse Crop Production & Engineering Design Short Course
Raft System – Deep water
Advantages
•
•
•
•
•
•
•
Significant buffering due to large volume of water
Well adapted for the production of short stature crops
pH and EC maintained at constant levels
Temperature of root zone optimized
Dissolved oxygen maintined with airstones
Ease of handling/harvesting
Maximized greenhouse floor space
Disadvantages
• Limited to crops like lettuce/basal/herbs
• Plants low to ground
2015 Greenhouse Crop Production & Engineering Design Short Course
NFT System
Advantages
•
•
•
•
Low capital start-up costs
Ease of handling/harvesting
Maximized greenhouse floor space
Plants are typically at waist level
Disadvantages
• Limited buffering due to small volume of water
• Difficult to control root temperature
• Disruption in water flow leads quickly to dehydration and wilting
2015 Greenhouse Crop Production & Engineering Design Short Course
Hydroponics – NFT System
Nelson & Pade, Inc.
E&T Farms Aquaponics.
Aquaculture Systems Tech., LLC
Continental Organics
2015 Greenhouse Crop Production & Engineering Design Short Course
Reciprocating System (flood and drain or just flood!
To ensure adequate aeration of plant roots, gravel beds
are operated in a reciprocating (ebb and flow) mode,
where the beds are alternately flooded and drained or
just flooded.
2015 Greenhouse Crop Production & Engineering Design Short Course
Reciprocating System (flood and drain)
Advantages
•
•
•
•
•
Lowest capital start-up costs
Ease of handling/harvesting
Grow a wide variety of crops
Maximized greenhouse floor space
Media beds at waist level!!!!
Disadvantages
• Media is or can be very heavy & expensive
• Disruption in water flow leads to dehydration and wilting.
although not a problem in flooded systems
2015 Greenhouse Crop Production & Engineering Design Short Course
Dutch Bucket System (bato buckets)
Dutch Bucket is basically a 2.5 to 3 gallon bucket with a
special drain fitting that maintains a small reserve of
nutrient at the bottom as a precautionary measure.
2015 Greenhouse Crop Production & Engineering Design Short Course
Drip System – Rockwool Slabs
These cucumbers are being grown in a slabdrip-irrigation system. The nutrient solution is
delivered via drip irrigation lines.
2015 Greenhouse Crop Production & Engineering Design Short Course
Aeroponics
In an aeroponics environment the plants grow with the
roots suspended in a misted solution of nutrients.
2015 Greenhouse Crop Production & Engineering Design Short Course
Vertical Gardens
Tower Gardens
In an aeroponics environment the plants grow with the
roots suspended in a misted solution of nutrients.
2015 Greenhouse Crop Production & Engineering Design Short Course
Perfect Medium
•
•
•
•
•
•
Holds a even ratio of air to water
Helps to buffer pH changes with time
Is easily flushed and re-wets easily after being dehydrated
Is reusable or biodegradable
Is inexpensive and easy to obtain
Lightweight and easy to work with.
Sometimes the Perfect Medium is NO medium
2015 Greenhouse Crop Production & Engineering Design Short Course
Commonly Used
Mediums:
Coco Peat
Coconut Coir
Rockwool
Perlite
Lightweight Expanded
Clay Pellets
Common Pea Gravel
2015 Greenhouse Crop Production & Engineering Design Short Course
Hydroponics – Raft System
Design Crieria: daily feed input/plant growing area
(Hydroponics makes up 75% of the system water volume)
Raft System: channel (raceway) with a 1 ft depth, usually 4 to 8 ft wide covered
by a floating sheet of polystyrene ( 4 ft x 8 ft x 1 to 1 ½ inches) for plant support.
"RULE OF THUMB???"
30 to 60 g of fish feed/day m2 of raft area
60 to 90 min water turnover rate
Aeration – airstones or diffusers
2015 Greenhouse Crop Production & Engineering Design Short Course
Hydroponics – NFT System
Design Crieria: daily feed input/plant growing area
(Hydroponics makes up small fraction of the system water volume)
NFT System: shallow flow of water, 1 lpm with 1% slope
"RULE OF THUMB"
Waste Treatment
15-40 g of fish feed/day m2 of trough area
1 lpm for rate per 10 ft tray x ~ 4 inch width
1% slope
2015 Greenhouse Crop Production & Engineering Design Short Course
Hydroponics – Reciprocating System (flood and drain
Design Crieria: daily feed media volume
(Hydroponics makes up small fraction of the system water volume)
Volume ratio of 1 ft3 of fish-rearing
to 2 ft3 of media
"RULE OF THUMB"
Waste Treatment
1 ft3 of fish fish rearing volume to 2 ft3 of media
(1/4 to ½ inch in diameter)
2015 Greenhouse Crop Production & Engineering Design Short Course
Design Crieria: daily feed input / plant growing area?
Golden Rule of Engineering Mass Balance
Production = Consumption +
Accumulation
Excess or Deficit in Nutrients
Plant Growth
Nutrients from Fish
2014 Greenhouse Crop Production & Engineering Design Short
Course
2015 Greenhouse Crop Production & Engineering Design Short Course
Free Macronutrients
(90 to 95% dry weight)
carbon (C): 30 to 50%
oxygen (O): 30 TO 48%
hydrogen (H): 6%
Macro-nutrients
(5 to 10% of dry matter)
Micro-nutrients
(less than 1% dry weight)
chlorine (Cl)
iron (Fe)
manganese (Mn)
boron (B)
zinc (Zn)
copper (Cu)
molybdenum (Mo)
nitrogen (N): 22%
phosphorus (P):
6%
potassium (K): 29%
calcium (Ca): 21%
magnesium (Mg): 6%
sulfur (S): 11%
pH Control
Calcium hydroxide
Potassium hydroxide
(Never Baking Soda)
2015 Greenhouse Crop Production & Engineering Design Short Course
High pH:
Decreases the availability of Iron, Manganese, Boron,
Copper, Zinc and Phosphorous
Low pH:
Decreases the availability of Potassium, Sulphur,
Calcium, Magnesium and Phosphorous
2015 Greenhouse Crop Production & Engineering Design Short Course
Compromise of Aquaculture
and Hydroponics
pH: 6.5 to 7.0
• Raise pH – Calcium Hydroxide or Potassium Hydroxide
• Lower pH – nitric, phosphoric or acetic acid
Temperature: 21 to 23 C ( 70 to 74 F)
• Tilapia usually: 25 to 28 C ( 78 to 84 F)
• Plants over 23C ( 75F) – slow growth & susceptible to funus
and phthium
2015 Greenhouse Crop Production & Engineering Design Short Course
Compromise of Aquaculture and
Hydroponics
Ammonia: < 3.0
• Species dependent
• High ammonia concentrations toxic to both plants and fish
Dissolved Oxygen: 80% saturation
• Tilapia: > 3.0 mg/L
• Plants just as important!!
Alkalinity: ~ 15 to 30 mg/L as (lowly buffered) CaCO3
• Low levels of CO2 compared to a fish system
• Never use Sodium Bicarbonate (Baking Soda), high sodium
levels
2015 Greenhouse Crop Production & Engineering Design Short Course
Compromise of Aquaculture and
Hydroponics
Electrical Conductivity: lower than hydroponics systems
•
•
•
•
Hydroponics: 1500-1800 (µS⋅m−1)
Aquaponics: 300 to 800 (µS⋅m−1)
Continuous generation of nutrients
Organic nature of nutrients results in a lower concentration of salts
Common Deficiencies:
• Potassium – potasium hydroxide
• Calcium – calcium hydroxide
• Iron – chelated iron
2015 Greenhouse Crop Production & Engineering Design Short Course
Greenhouse
Construction
Team: Alison Burton, Isaac Hung, Aaron Tirado
Agricultural & Biosystems Engineering
University of Arizona
Design
2015 Greenhouse Crop Production & Engineering Design Short Course
Dr. James M. Ebeling
21 years – Cornell University Short
Course
June 23-25, 2015. Newburgh, New York
Dr. Michael B. Timmons
Cornell University Professor
2015 Greenhouse Crop Production & Engineering Design Short Course