Our house is not connected to a town water supply, we just have a water tank under our house (approx. 12000 litres / 3000 gallons). We have it filled from a water truck every 3-4 weeks. Apparently the water truck gets the water just from a rural well, and it is full of minerals (I've been told it's calcium, but I don't know for sure). These minerals are clogging up our pipes (mostly seems to affect the toilets and sinks).
A friend told us we could possibly add some kind of water softener to try and remove (?) the minerals to stop or reduce the clogged pipes. We went to a Home Depot and asked there, and they pointed us to Water Softener Salt Pellets (link to product on US HD website). The assistant at Home Depot said he believed it should do what we wanted (he got on google to figure it out...) but he couldn't find how much to add to our water tank. He said usually people have a water softener filter system and the stuff is added to that, but thought adding it directly to the tank should work. At this stage a water softener system isn't an option (at least the ones we looked at in the Home Depot store)
Will adding the Water Softener Salt Pellets to our tank actually help, and if so how much do we add? Would we just add it when we get the tank filled, or every day/week?
The water is not used for drinking/food (cannot be consumed), it is only used for bathrooms and laundry. We live semi-rural in the desert (not in the US); this is our only possible water source.
We live in Mexico and access to experts in our area is difficult, however we can travel into the US if needed to buy/import supplies.