Colour (first and third panel) and metallicity (second and fourth panel) distribution for 16 F3D galaxies that have a sufficient number of GC candidates in the ACSFCS catalogue from Jordán et al. (2015) to create a well sampled distribution. MDFs were inferred from the colour distributions using Eq. (3) with the best-fit parameters from our default CZR (Table A.2). The histograms are coloured based on the stellar mass of the host using three mass bins: log(M_Host/M_⊙) < 10 (pink), 10 ≤ log(M_Host/M_⊙) < 11 (blue), and log(M_Host/M_⊙) ≥ 11 (purple). The red histograms show the GCs in our sample. In the top left corner of each panel, the distributions are classified as bimodal (“BI”) or unimodal (“UNI”) based on the GMM test described in the text.