800+ ppm out of well, limited options

[Pushrod Monkey]

Buy plastic 50 gallon drums with removable lids. Food grade used are fine. You can buy everything to make slow sand filters at Home Depot. Instructions all over the internet. They’re extremely effective. Buy a couple so you can “recharge” one while using the other. Best bet is to build several so you have at least 15-20 gallons per day of water.

 

[frogyrogy]

They get a bit pricey but you can buy activated carbon filters for bigger systems. I helped install one for some chicken houses that filtered 200 gpm, was plumbed using 3" pipe.

 

[Ponky]

Aquadrum 55 Gallon Drum Pump and Filter System

Finally a water filter and pump system for 55 Gallon Drums. The Duraflo filter gives you 250 gallons of crystal clear water, at a rate of up to 1 gallon every 3 minutes. And the filter can be used over and over again - no expiry dates.

www.bridensolutions.ca

This isn't exactly it. But I think it's close. There's agricultural stuff on PDF that explains scaling up. Looks to be a whole Industry.