A Comparison of Plant Growth Rates between an NFT Hydroponic System and an NFT Aquaponic System

Ward Ward,Lennard Lennard

doi:10.3390/horticulturae5020027

Abstract

A comparison of leafy green plant species’ (lettuce (Lactuca sativa L.), dill (Anethum graveolens L.), rocket (Eruca sativa), coriander (Coriandrum sativum L.), and parsley (Petroselinum crispum)) growth rates was performed between an Nutrient Film Technique (NFT)hydroponic system, using standard commercial nutrient solution, and an NFT aquaponic system, using fish waste from Grass Carp, (Ctenopharyngodon idella) which provided the majority of the nutrients required by the plants. The results demonstrated that the aquaponic method performed well, and, in many cases, the growth rates produced were similar to those of the hydroponic method. Lettuce growth was compared across three seasons (summer, winter, and spring), and, in all cases, the aquaponically-grown lettuce equalled, or bettered, the hydroponic equivalent. Herb growth was compared over a five-month period (February to June—summer/autumn), and in 17 out of 23 comparisons, the aquaponic method produced results similar to those of the hydroponic method. Thus, while the NFT method may not be the most appropriate technical approach for aquaponic integration, the results suggest that the overall aquaponic method has the potential to produce plant growth rates at least equal to those of standard hydroponics.

Highlights

Aquaponics is a system of integrated, tank-based, aquatic animal culture and hydroponic plant culture wherein the majority of nutrients required for plant growth arise from the waste derived from feeding fish [1,2]
The system water chemistry parameters are represented by a number
The herb culture comparisons were only performed across five months of the year; the results demonstrated that a large range of commercial herb varieties adapted positively to the aquaponic method, and should be expected to perform very well across at least half of the calendar year

Summary

Introduction

Aquaponics is a system of integrated, tank-based, aquatic animal (typically fish) culture and hydroponic plant culture wherein the majority of nutrients required for plant growth arise from the waste derived from feeding fish [1,2]. Few studies are available that directly compare aquaponic plant production or growth rates to soil-based culture or hydroponic culture. Aquaponics is a water-based nutrient delivery approach, and is, similar to standard hydroponic production methods. Hydroponic plant culture methods are some of the most productive methods available for horticulture [14], and serve as a good standard production approach for comparison to aquaponics. Hydroponics is an established, commercial, financially viable horticultural production approach used broadly around the world, and has capital expenditure and costs of production similar to aquaponics, in terms of plant culture. If plant production rates within aquaponics can be established relative to hydroponics, this may shed some light on the potential commercial and financial viability of aquaponic plant production methods and techniques

Methods

Results

Discussion

Conclusion