[BCReefer]

Thanks everyone. I think I will start off with the cheap one and take some water to J&L and get them to test. If the reading are close then I will keep the cheapo. If I see larger variances then I will look at a more expensive system.

When I worked in the hydroponics business, we had TDS digital testers. They are about $150.00 ?? CDN$ and are on at all times. anyone else using one?

Thanks
Patrick