Comment: How to Settle Muddy Water

Going back to our farming days we used to settle Dam (very muddy) water in a 2000 Gallon Galvanised Tank by filling tank and then throwing two handfuls of Aluminium Sulphate over the top. Water as clear as crystal was ready to use next day. Tank was connected to house and used for everything (including laundry)with the exception of drinking. Rainwater tank was connected to house for drinking and cooking etc.
Also tried settling the whole dam by spraying a mixture of Alum over it which also worked well except the Carp had it all churned up again very quickly.
Not sure but Gypsum comes to mind that we also may have tried that but can't recall the results. (was some 40-50 years back)
Regards
Rodney