Good PH Tester

[Joshsmit56001]

I found some PH testers on ebay and was wondering which is a goood one.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3803874598&category=26230

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2386978598&category=20758

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2385859429&category=3212

Also there are some with calibrations kits with three different types of calibration levels, 4.0, 7.0, and 10.0, which do I calibrate it at??

TIA,
Josh

 

[Biggen]

IMO, none of those are good pH meters. Those are cheap Hanna units that have an accuracy of +-.2. You can do a lot better with your money. You want to make sure you get a meter with an accuracy of at least +-.1 or better.

Also there are some with calibrations kits with three different types of calibration levels, 4.0, 7.0, and 10.0, which do I calibrate it at??

This depends on the meter. Those meters you linked to on eBay are single point calibration. That means you one use one buffer (probably 7.01) to calibrate it. Better meters use a two point calibration method (7.01 & 10). This allows the meter to have better accuracy.

 

[captivereefs]

American marine makes the pinpint PH monitor. THey are very nicely built and perform fawlessly and accurately.