Is it possible to use 2 shields on one Arduino board?

If yes then would these two shields work? http://australianrobotics.com.au/products/ec-shield-assembled https://www.tindie.com/products/rezahussain/arduino-ph-shield-by-dormant-labs/

I was going to make a project that could measure EC and pH using one board. Any tips for a beginner?

You have two things to consider. 1) Can they physically be stacked, some shields like the ph one can't have anything on top of it. The other one has pins and headers so it can. 2) Are the same pins used for both shields? If so can one be changed to use other pins?

Don't forget to check whether your power supply is adequate to handle all three boards.

Hi, I'd follow Mike's suggestion and list all the pins used by each shield and their functions. Check for conflicts.

Get each shield working separately with some simple test sketch.

Here's some guidance on combining sketches/shield: http://arduino-info.wikispaces.com/CombiningArduinoSketches

How exactly would I know what pins are used and if they are compatible? Or would I be better off not using the shields?

Hawhaw: How exactly would I know what pins are used and if they are compatible? Or would I be better off not using the shields?

You need to go to site selling the shield, and download the documentation/datasheet, and it should tell you what pins are used. If the site doesn't have documentation available, consider buying a different shield. Basically, most shields are just for convenience. They fit into the Arduino, which spares you the need of having to provide all of the components on the shield.

Is it possible you might get pH ground loop problems since you are sharing pH and EC grounds on same board? YES

So I would be better off not using the shields?

Hawhaw: So I would be better off not using the shields?

No.

If you can't cope with what I said how are you going to cope with building your own circuit.

Good point. Thanks.

If you power the shields in parallel they should be fine off one adapter?

syphex: If you power the shields in parallel they should be fine off one adapter?

Only if the adaptor can supply the required current and the supply decoupling is enough so you do not have a ripple problem. But otherwise yes.

Rather than start a new topic, I want to bump this post current and expand a bit if possible. I am also a newb, I have an UnoR3, with mega 2650 & ethernet shield being delivered, and I want to keep expanding my collection as long as it's heading in my desired direction. I am into indoor gardening and am hoping to one day build a "control every" device(s) that automates every electrical aspect of indoor gardening.

With that said, I am wanting to also purchase functioning EC(TDS) and pH shields/stamps, however, it appears there are only a small handful of manufacturers that make these, and the ones made will only monitor a single probe, albeit DIY probes or those on BNC connectors. My biggest concern is that I would have to buy a shield/stamp for each probe I buy or build and to think I will need an EC AND a pH probe for each of my 7+ reservoirs would financially break my back.

So before I get into all that, does anybody know if it is possible to build a circuit that a Mega 2650 (or Uno R3) can control a single shield or stamp that in turn could be fed a series of signals from probes in different solutions and still populate an accurate result to the serial monitor? I have a 750 watt ATX that I still need to mod, but I expect I will have more than adequate power for all devices that need some extra volts/amps.

myggle: Rather than start a new topic, I want to bump this post current and expand a bit if possible. I am also a newb, I have an UnoR3, with mega 2650 & ethernet shield being delivered, and I want to keep expanding my collection as long as it's heading in my desired direction. I am into indoor gardening and am hoping to one day build a "control every" device(s) that automates every electrical aspect of indoor gardening.

With that said, I am wanting to also purchase functioning EC(TDS) and pH shields/stamps, however, it appears there are only a small handful of manufacturers that make these, and the ones made will only monitor a single probe, albeit DIY probes or those on BNC connectors. My biggest concern is that I would have to buy a shield/stamp for each probe I buy or build and to think I will need an EC AND a pH probe for each of my 7+ reservoirs would financially break my back.

So before I get into all that, does anybody know if it is possible to build a circuit that a Mega 2650 (or Uno R3) can control a single shield or stamp that in turn could be fed a series of signals from probes in different solutions and still populate an accurate result to the serial monitor? I have a 750 watt ATX that I still need to mod, but I expect I will have more than adequate power for all devices that need some extra volts/amps.

Thanks, but I need expansion and cost efficiency.

How about what these user did: A Mega screw shield on an ethermega and a relay shield, lots of options for connecting and connecting.
Being used on a boat, so installed in a polycase.com watertight box with glands for the wires that go in/out.