Hi all, I am using Tropica soil powder as my substrate and am really struggling to suck the fish poo/miscellaneous debris out of it with my gravel vac. Does anyone have any tips? My problem is that the substrate enters the tube and clogs it up, which then prevents anything else from getting in (other than water). Wondering if I'm perhaps going at the substrate at a dodgy angle - my tank is 145cm tall and I'm only 160cm, so water changes are a bit tricky!!