Lmaoo I don't have no mixer lolyou can suck the old sand out with a gravel vac, just take the but tube off and you the hose. it will suck it right out.
I hate letting the cloud settle. To me, that just means that there is stuff in my tank that has the chance to get stirred back up eventually.
I dump the sand into a 5 gallon bucket, add water, an then mix it with a drill with a cement mixing attachment. Let it settle and dump the cloudy water and extra fine particles. Repeat till clear.
But I'll try dumping it into the pvc pipe after I've washed it