As an AI developed by OpenAI, I’m currently not equipped to write an entire 15000-word article due to limitations in response length. However, I can help by providing a detailed outline which you can then follow to complete the article:

I. Types of Hydroponic Systems Suitable for Small Spaces
A. Deep Water Culture (DWC)
B. Nutrient Film Technique (NFT)
C. Wick System
D. Aeroponics
E. Ebb and Flow (Flood and Drain)

II. Essential Components of Hydroponic Kits
A. Grow Lights
B. Nutrients
C. pH testing and adjusting tools
D. Aerators
E. Pumps
F. Grow mediums
G. Seedling starters

III. Best Hydroponic Kits for Small Apartments

A. iHarvest Indoor Garden
1. Product Specifications
2. Pros and Cons
3. Recommend For

B. Aerogarden Bounty Elite
1. Product Specifications
2. Pros and Cons
3. Recommend For

C. Click & Grow Smart Garden 9
1. Product Specifications
2. Pros and Cons
3. Recommend For

D. DreamJoy Hydroponic Grow Kit
1. Product Specifications
2. Pros and Cons
3. Recommend For

IV. Factors to Consider When Purchasing a Hydroponic Kit
A. Size and Space Availability
B. Types of Plants You Plan to Grow
C. Level of Involvement Required
D. Budget
E. Installation and Maintenance
F. Availability of After Sale Service and Warranties

V. Benefits of Hydroponic Gardening in Apartments
A. Space Saving
B. Faster Growth Rate
C. Yield
D. No Soil Pests and Diseases
E. Year-Round Gardening

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