Flux Density, SEFD (Jy)                                           2.1                    0.4

  : Properties of the two phases of the SKA (see footnote \[footnote:ska\]).

\[tab:specs\]

Filament catalogues from SDSS, 2MRS and 6dF {#sec:filcat}
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Given their high sensitivity, both SKA1-mid and SKA2 will be able to detect extremely faint galaxies and therefore it would be possible to trace almost the complete cosmic web within their surveys. However, until data from such surveys becomes available, it is necessary to resort to existing galaxy surveys in order to determine the location of filament spines on the sky. In this case, we use the galaxy catalogues from three large-area galaxy redshift surveys to identify realistic filaments as a proxy for what the SKA should be able to detect in its survey volumes.\
One of the largest and most dense samples of galaxy redshifts was obtained by SDSS. We adopt the filament catalogue that was described in @art:tempel14, whose data is publicly available. The catalogue uses a sample of 499340 galaxies in the redshift range 0.009 $\leq z \leq$ 0.155 and is limited in magnitude by the spectroscopic sample [@art:ssdssspecsamp].\
Additionally, we applied the Bisous model to the galaxy sample of the 2MRS survey and to a combined sample of 