The Puffer Forum

I am going to buy a tds meter to be able to test my ro-di filters. I looked on ebay and there are plenty different brands for around $15 or so. Are they going to be just fine or are they all junk?

I bought this one and it works fine, it was the cheapest I could find

http://www.ebay.co.uk/itm/Digital-TDS-M ... 56421e54b7