Cant find sensors for pH testing and salinity (refractometers)

JodyDaniela

Hello everyone.

I am looking for a pH probe to interface with the bs2 as well as a digital refractometer. Can anyone help me find some?

Thx for reading!
-Jody

Leon

http://www.google.co.uk/search?source=ig&hl=en&rlz=&=&q=ph+sensor&aq=0&aqi=g10&aql=&oq=pH+se&gs_rfai=

John R.

The topic of pH sensors has come up here regularly, and there are two basic ways to go about it, and a couple "out of the box" methods. One is to spend a lot of money on the probe, and get one that is pre-amplified (or find a commercial amplifier/conditioner) and sends out a signal (voltage or otherwise) that is directly readable by a Stamp. The other is to get a "normal" pH probe (with BNC connector) and build the amplifier circuit yourself. The probes have a very high impedance, and you generally need to build the circuit on an actual circuit board, not a bread board. Here's one good source for information from Dr. Allen's site: http://www.emesystems.com/OL2ph.htm

Outside the box, you could also use either test strips, titration or color-metric tests and use one of the color sensors to read the results.

There have been a few ideas thrown around on salinity, but rather than based on refractometer technology, there have been based on hydrometers, and using some type of sensor to measure how high the tube is floating. You may also be able to buy a commercial meter, and interface it.

There are a fair number of forum members working on aquarium monitoring tools, so once you get "zeroed in" on a direction, or have more specific questions, let us know, and we'd be glad to kibitz, as well as hear what works/doesn't work for you.


John R.