PPM tester

anyone know where I can get a decently cheap ppm tester?

Ebay. I was looking at some PH and ppm pen testers and some are priced pretty decently.

There used in the window cleaning industry also to measure TDS. Average from $25 to $60. Try here
It's the cheapest one I have found

Window Cleaning Shop

whats tds?

TDS is total desolved solids. If thats what you are looking for? PPM is a measurement of parts per million. TDS is what floats in your water from the tap. IE 250 TDS PPM.

yeah im looking for ppm but im wondering if a tds tester would use the same scale

Yes, it will. A TDS meter measures TDS (Total Dissolved Solids) and expresses this as PPM (Parts per million.)