# Investigating the Effects of Fish Effluents as Organic Fertilisers on Basil (_Ocimum basilicum_)
## 3 Results  
### Plant Growth and Yield  
All plants grew in height and weight (Figure 2), and only one plant died of unknown causes (in replicate IT2). Visually, and on measurement, it was evident that the plants from treatment IT--plants grown in compost-free substrate and irrigated with tap water--were much smaller and less developed than the rest, with an average height of 15.06 cm, compared to the other treatments ranging between 23.24 cm and 25.19 cm (Figure 3). The growth yield values, including % of nitrogen by dry weight, are shown in Table 3, while the values in boxplot form are shown in Figure 4.  
Figure 3: Comparison of randomly selected trays, one from each treatment, showing the clear visual difference of treatment IT, top left photo, from the rest of the treatments, reflecting its significantly lower product yield. Figure 2: Complete display of the two shelves where the plants were grown, showing the individual replicates (black trays), five pots per tray, and grow lights on the last day of the experiment. In all measurements, the residues of the model were found to be normal, and no outliers were identified. Based on the above results, substrate, fertiliser, and the interaction between substrate and fertiliser all had a significant effect (\(p<0.05\)) in all measurements undertaken, except for the nitrogen dry weight percentage, where only substrate and fertiliser had an effect, but not the interaction between them. The fish sludge treatment (FS) outperformed the fish water treatment (F) and the tap water treatment (T) for leaf biomass and nitrogen dry weight percentage in both substrate types (Table 3), with the following pattern: FS \(>\) F \(>\) T. For the leaf biomass measurement, in fact, and for the compost-free substrate, fish sludge (FS) produced an average biomass of 28.25 g, fish water (F) 23.75 g, and tap water (T) 7.12 g. For the compost substrate, the average leaf biomass was 35.75 g for fish sludge (FS), 31.62 g for fish water (F), and 23.5 g for tap water (T). For the nitrogen dry weight percentage, in the compost-free substrate, fish sludge (FS) produced an average percentage of 4.44, followed by 4.0 for fish water (F), and 2.55 for tap water (T). In the compost substrate treatment, fish sludge (FS) produced a percentage of 4.9, followed by 4.4 for fish water (F), and lastly by 3.01 for tap water (T). The same trend is observed for the stem diameter measurement of the compost-free substrate, where fish sludge (FS) produced an average diameter of 2.64 mm, followed by fish water (F) at 2.75 mm, and tap water (T) at 2.73 mm. However, in the compost substrate the fish water treatment (F) performed better than the fish sludge treatment (FS) for stem diameter (2.75 mm vs. 2.64 mm) and plant  
Figure 4: Boxplots for plant height (**top left**), leaf biomass (**top right**), stem diameter (**bottom left**), and nitrogen weight % (**bottom right**), with fertiliser type (F: fish water; FS: fish sludge; T: tap water) and substrate type (I: compost-free substrate; C: compost substrate). Sample sizes (n) in the top right corner of each plot. \begin{table}
\begin{tabular}{l l l l l} \hline
**Treatment** & **Height (cm)** & **Stem Diameter (mm)** & **Leaf Biomass (g)** & **Nitrogen (\%)** \\ \hline IT & 15.06 \(\pm\) 1.75 b & 1.84 \(\pm\) 0.13 b & 7.12 \(\pm\) 0.85 d & 2.55 \(\pm\) 0.18 c \\ IF & 23.85 \(\pm\) 2.43 a & 2.39 \(\pm\) 0.23 ab & 23.75 \(\pm\) 1.66 c & 4.00 \(\pm\) 0.21 b \\ IPS & 25.19 \(\pm\) 2.85 a & 2.51 \(\pm\) 0.35 a & 28.25 \(\pm\) 1.66 b & 4.44 \(\pm\) 0.42 ab \\ CT & 24.58 \(\pm\) 2.83 a & 2.73 \(\pm\) 0.29 a & 23.50 \(\pm\) 1.69 c & 3.01 \(\pm\) 0.36 c \\ CF & 24.56 \(\pm\) 1.21 a & 2.75 \(\pm\) 0.36 a & 31.62 \(\pm\) 1.93 ab & 4.40 \(\pm\) 0.15 ab \\ CFS & 23.24 \(\pm\) 2.42 a & 2.64 \(\pm\) 0.28 a & 35.75 \(\pm\) 3.07 a & 4.90 \(\pm\) 0.26 a \\ \hline \end{tabular}
\end{table} 
Table 3: Mean values and standard deviation values (\(\pm\)) for growth measurements.