I live in mahasarakham and I'm

Looking to purchase a RO filter can

Anybody point me I'm the right direction

You should check first of all what the water which you are going to filter is like. We had a RO filter (in Buriram), and it clogged up so quickly with lime that it simply wasn't practical. We tried carbon filters and some others, but nothing worked.

Finally we settled for buying artesian water, and topping it up with rainwater,

My water is drinkable now,I just need to reduce the salt content which can only be achieved with a RO system

If you have lots of white scaling after water dries, it's probably calcium. If the water has a reddish-brown tint, that's iron. If a RO system scales up, the system probably needs a a mechanical filter, then a "softener" before the RO.

bad water -> media filter -> softener -> Membrane Filter ('RO') -> Carbon filter -> UV (Ozone) -> good water

Real RO removes dissolved solids, most 'RO' systems here are actually 'ultrafiltration'. Look up the differences in Wikipedia -- it can get complex.

Carbon filters should be placed down stream (after) RO since it is designed to remove organics (odors and tastes).

Ozone from UV systems kill biologicals.

My water is drinkable now,I just need to reduce the salt content which can only be achieved with a RO system

A RO system to removed sodium chloride is pretty complex. The 'salt' is dissolved, so an ultra-filtration membrane won't remove it. I doubt that salt was making your water undrinkable. Did you take water samples for testing?

As an aside, distillation also removes sodium chloride.

slightly off topic, where can I get a reliable, independent laboratory test done for my water? Nobody seems to bother about this much, you just get told, 'don't drink the tap water'. I'm sure you can get rid of most stuff that's in the water, but what about pesticide and herbicide residues for instance? Arsenic and mercury?

I use a quite large activated charcoal filter, it's over a meter tall and about 14 cm in diameter. The water from that goes through a ceramic filter and that's what we drink. It is rain water collected off a metal roof and stored in a 1,500 liter fiberglass tank. My wife fills plastic Coke/Pepsi bottles from there and keeps them in a small refrigerator. No ill effects after 3 or 4 years.

I used to buy the big translucent plastic bottles from a water company but stopped that when I found mosquito larvae swimming in a sealed bottle.

I think rain water is the best because you don't have to worry about heavy metals, pesticides or minerals.

I use a quite large activated charcoal filter, it's over a meter tall and about 14 cm in diameter. The water from that goes through a ceramic filter and that's what we drink. It is rain water collected off a metal roof and stored in a 1,500 liter fiberglass tank. My wife fills plastic Coke/Pepsi bottles from there and keeps them in a small refrigerator. No ill effects after 3 or 4 years.

I used to buy the big translucent plastic bottles from a water company but stopped that when I found mosquito larvae swimming in a sealed bottle.

I think rain water is the best because you don't have to worry about heavy metals, pesticides or minerals.

+1

slightly off topic, where can I get a reliable, independent laboratory test done for my water? Nobody seems to bother about this much, you just get told, 'don't drink the tap water'. I'm sure you can get rid of most stuff that's in the water, but what about pesticide and herbicide residues for instance? Arsenic and mercury?

From an old thread

You can ask for help from ..

Department of Agriculture Extention in Bangkok and Udon-station.

www.doae.go.th

Or at the Irragtion Dept. in BKK and Khonkhen station.

www.rid.go.th

Or. Land Development Dept. in BKK and Khonkhen station.

www.idd.go.th

thanks, there are many threads here. I look forward to visiting the erection Dept. you may have misspelled it.

slightly off topic, where can I get a reliable, independent laboratory test done for my water? Nobody seems to bother about this much, you just get told, 'don't drink the tap water'. I'm sure you can get rid of most stuff that's in the water, but what about pesticide and herbicide residues for instance? Arsenic and mercury?

From an old thread

You can ask for help from ..

Department of Agriculture Extention in Bangkok and Udon-station.

www.doae.go.th

Or at the Irragtion Dept. in BKK and Khonkhen station.

www.rid.go.th

Or. Land Development Dept. in BKK and Khonkhen station.

www.idd.go.th

Erection?

You asked so I posted a quote from another thread. Sorry for the favor -- will not repeat the offense.

yes, sorry about the joke, thanks for the reference. I was actually wondering if there were any independent laboratories around.

You should check first of all what the water which you are going to filter is like. We had a RO filter (in Buriram), and it clogged up so quickly with lime that it simply wasn't practical. We tried carbon filters and some others, but nothing worked.

Finally we settled for buying artesian water, and topping it up with rainwater,

Just out of curiosity Birdy, isn't purchasing separate artesian water a bit costly?.....or not?