Here’s a list of all the materials that I used to make the Hydropi Pool Monitor.

The Hardware

• Raspberry Pi (Rev 2 or 3)
• Raspberry Pi power supply
• USB WiFi adaptor (required for non Rev 3 Raspberry Pi’s)
• 8Gb Micro SD card

The 4 items above can also be purchased in a variety of kits

• Breadboard
• Jumper wires

Sensors

• 2 x DS18B20 Temperature Sensors

Atlas Scientific Sensor Circuits

• pH
• Oxidation Reduction Potential (ORP)
• Electrical Conductivity (EC)
• Temperature Sensor (Optional)

Atlas Scientific Sensors

• pH
• Oxidation Reduction Potential (ORP)
• Electrical Conductivity (EC)
• Temperature Sensor (Optional)

These can also be bought as kits that include the circuit, BNC socket, sensor and calibration liquids all in one

 pH Kit

 Electrical Conductivity (EC) Kit

 Oxidation Reduction Potential (ORP) Kit

Temperature Kit

Atlas Scientific’s documentation states that their pH, ORP and EC circuits will work with any off the shelf BNC probes, I haven’t tried connecting any other probes to the circuits so I can’t say whether they will work or not but if your budget doesn’t stretch to the Atlas probes the Neptune series of probes are cheaper and appear to have good reviews.

• 3 x Sensor circuit mount to BNC board
• 2 x Power isolation circuits

The 2 items above are now incorporated in one board providing both power isolation and sensor circuit mounting, this will free up a lot of breadboard space and also save you money, you will need one for each sensor you are connecting.

Electronic Components

• 4 x 2.2kΩ Resistors
• 4 x 2N3904 NPN Transistors

AC Power

• 4 Way relay module
• Surface Mount AC power socket (Country specific, required to plug in the Pi power supply)

For the following 3 items I basically bought one of these and broke it down to use it’s parts, I’m sure that something similar is available in most countries with the required socket type.

• 10A circuit breaker or 20A circuit breaker
• 4 x AC outlets (US)
• AC power cable (US)

When it comes to AC power the required items are quite country specific so I have only placed links as examples, you will need to do your own research to find the appropriate parts for your project,  and again if you are not use to working with AC power then please get the advice of a professional.

Miscellaneous

• Wire Connector Screw Terminal Barrier Block
• 1 x plastic enclosure 250(l)x210(w)x130(h) (Minimum)
• 1.5mm (16 AWG) AC power cabling (Available from most hardware or electronic stores)
• Electrical Insulated Crimp Terminals
• Waterproof Cable Glands
• M3 Plastic mounting nuts, bolts and standoff’s
• Cable ties

Tools (Optional)

• Soldering Iron
• Electrical Insulated Terminal Crimper
• Electronics Tool Kit

Software

• Raspian
• Apache Web Server
• MySQL
• PhpMyAdmin
• Ninja IDE (Optional, used for writing python code)
• WeBuilder (Optional, used for coding webpages)
• Bootstrap (Optional, used as a framework for creating webpages

These are all the items that I used to create this project, obviously there are other possible arrangements, if you have thought’s feel free to leave a comment below.