Top tip for sand users:
Do you get Poop all over the sand, Do you wish it would remove itself to where the plants are (and can use it)
Have the spray bar horizontal positioned centrally on the back and 2 inches from the water's surface.
Point the holes directly towards the front.
The current (without disturbing the surface too much and releasing all that valuable CO2) will go to the front, then down, then to the sides, then the back, where it will either enter the filter or return to the top, taking most of the poop with it and depositing it where the current is at its lowest. i.e. the Sides and the back.
Of course I do still do water changes once a week, but there is virtually no poop on the sand at the front during the week, and I leave it in the plants as they use the nutrients.
As my reference points
At the weekend I pointed the holes at the back of the tank, and by nightime there was poop everywhere. I readjusted the holes to the front and within one hour, the viewable sand section was clear again.
Also this is how I noticed that my 21 month old son had turned the filter off yesterday, when I thought why is there a load of poop in the front of the tank, again filter on and 1 hour later clear.
I use a Fluval 1/2/3/4plus spraybar on a Fluval 3 Plus Internal in a 125Ltr Tank