Hydroponics systems at Gateway Technical College include Dutch buckets, nutrient film technique (NFT), ebb and flow rafts, aeroponics towers, and ZipGrow vertical walls. Rockwool is used to start seeds, providing inert support in nutrient solution. Plants require 16 nutrients delivered through fertilizers adjusted based on crop type and growth stage. The systems are suitable for a variety of crops including tomatoes, peppers, herbs, and leafy greens.

1. Hydroponics at Gateway Technical College
and Beyond

4. The Basic Idea
• Nutrients added to water in
reservoir/tank
• Water pumped to container
holding plant roots
• Water flows back to tank by
gravity
• Air stone adds oxygen needed by
plants for respiration and to
keep water from becoming
stagnant

5. Rockwool
• Seeds are started in rockwool and
transplanted into various systems
• Rockwool is an inert material
holding plants up in nutrient
solution
• No bio activity to plug lines or foul
water.
• No nutrient charge

6. Seed Starting in Rockwool
• Rockwool needs to be soaked for
several hours to lower pH
• Add pH buffer to bucket of water
and adjust to pH5.5
• Add weak nutrients solution to
660ppm or .5-1 EC
• Soak cubes for 30 min -2 hrs
• Place rockwool cubes in web tray
and seed. Don’t squeeze rockwool
• Light and 70-80 deg

7. Nutrients
• Plants need 16 nutrients to grow
• Nitrogen – Phosphorous – Potassium = macronutrients
• Micronutrients – very small amounts needed
• Nitrogen vegetative – ‘green’ growth leaves, stems, chlorophyll
• Phophorous – rooting and flower initiation
• Potassium – stress resistance, cell strength, quality

8. Nutrients and Fertilizers
• Amount and timing vary according to crops grown
• Leafy greens/herbs vs fruiting crops - tomato, cuke, medicinals
• Change ratio at flowering or lower fertilizer level

9. Fertilizer Formulations - liquid
• Premixed stock solution.
• Convenient – use directly from
bottle, no pre-mixing
• Dilute – paying to ship a lot of
water
• Expensive for large systems

10. 9-7-37
9% nitrogen
7% phosphorous
37% potassium
Complete micronutrients and gel technology to coat bare roots in solution
For product information sheet click here

11. Gateway has examples of 4 major systems
1. Dutch Bucket or ‘bato bucket’
2. Nutrient Film technology or NFT
2. Ebb and Flow or Raft System
3. ZipGrow Vertical System – wall and upright
4. Aeroponics Tower Garden

12. 1. Dutch Buckets, bato Buckets

13. Crops
• Larger fruiting crops
• Tomato
• Pepper
• Basil
• Cucumber
• Medicinals – Cannabis, Ginseng, Goldenseal and others, Tobacco for
producing vaccines

17. Trellising Tomatoes

18. Pruning
One main stem only
Side shoots and suckers
should be removed weekly
EZ to lag behind.
Fruit production down 50%

19. Aeroponics – Tower Garden

21. • Warm season or cool season?

22. Crops
2 different uses:
1. Homeowner or restaurant system with lights
2. Commercial indoor with or without lights (energy $)
• Leafy greens – lettuce, kale, spinach
• Leafy herbs – basil, parsley, chives, cilantro, marjoram
• Baby bok choi, mustard, kale
• Warm or cool season?

23. Nurient Film Technology - NFT

24. Crops
• Leafy greens
• Lettuce – head
• Herbs – basil
• Animal fodder – gas fed cows in winter, chickens

27. Ebb and Flow or Raft system

28. Ebb and Flow Raft System

29. Ebb and Flow Microgreens

30. ZipGrow Vertical

32. Zip Grow Wall

33. Crops
• Leafy greens
• Leafy herbs
• Herbs – basil, rosemary, cilantro
• Strawberries
• Cool or warm season?
• Daylength – day neutral

34. Aquaponics

35. Growing Power

36. Nelson and Pade