This thing sounds like a good piece of kit, I carefully siphon the poo and crud from my sand substrate only to find the next day or so a load more has been washed out from the rocks or where ever.
Will it siphon up the poo from efficiently from a sand substrate ?
Nick my substrate is crushed coral sand but it works a bit like the python ie swirl it above the sand and the poo rises. If the sand starts to go up lift up slightly away and it falls back down. I never worried about losing a bit of sand tbh and if you've still got your playsand then it's cheap to replace plus it would take a lot of vacs to remove a significant amount that you'd notice. How was your hols?