Bluetooth sensors with app

Hey all,

I want to make a simple BlueTooth app that monitors my fish's 5- 5-gallon tank's ph, temperature, NO-2/-3 levels, and switches on/off the heater at the power source (ugh... custom/or preset 15 watt heaters are almost non-existent) based on the temp, and notifies me when any of these are above, or below, the desired level. Anything that comes in direct contact with the aquarium/water will need to be non-toxic and safe (no heavy metals, sharp edges, or coated with a fish-safe rubber). I know I will need

  • Sensors
    • NO-3
    • NO-2
    • Thermometer
    • Ph Tester
  • Some sort sort of switch?

Where can I get these?
Will I need an arduino kit?
What if I'm out of range of the BlueTooth-can I still get it to notify me like through wifi?
Is there anything else I will need Bluetooth-wise?

I have the basic coding for the notifier, graphing, and the UI down, but I'm a complete and utter noob to Bluetooth- We'll burn that bridge later...

@Mark_Parente, I know you work with fish, Any suggestions?

I will be using the Bluetooth/Ble Extension, and @Taifun's Notifier extension.

This will be for my veiltail betta fish, and my black racer snail, and MAYBE a female betta and a golden mystery snail. This may be a little over the top for a betta and snails, but I love them that much, and it would be a basis to build on for future bigger community tanks. And it'll save money, and less stress for the fish.

Sounds Great!!!

I think Arduino would be the best solution, as it's easy and cheap.

I think a relay switch would do the work.

An Arduino or other board that contains uC will be needed. The sensors themselves are not enough, the arduino has to read the values from the sensors and process them. Then send the data to the UART, e.g. via the BT module to the phone. The application on the phone can be used to control the values and to set the temperature in the aquarium. You can also add a lighting control function. If you want, we will help in the forum with this project and a nice tutorial will be created.

Thanks @Patryk_F and @Kaustubh_Rakhade for your quick responses. Sorry about the late response- I was in school. Sure, I would like you to make an example. Thank You! Will it include what I need to buy?

Search the internet today for the sensors you wrote about and put a list here of what you found and we will verify and confirm.


I did that. Here's the list. Most of it is from Cooking hacks/Libellium.

Note: Use ctrl-f and then search the term

See here and here. I also couldn't find an actual page to buy them from... Any idea?

First, let's specify what you need. In the first post you wrote NiO2 and now NO2.
I do a little research on the internet. See what I found:

I think the temperature and lighting will be easy. The rest of the sensors may be hard to come by.

Oops. NiO is Nickel (III) Oxide, Nitrate/Nitrite is NO-3/-2. I'll fix that...

I agree with you on that. I've decided that it would be easiest with starting on making the thermometer work to turn on/off the heater, and a timer for the Lights. I might also add an auto dimmer for the lights. The sensors (other than the thermometer) will likely not happen, I just don't have the money for most of them.

Looking at the Arduino thread, and on other threads, I've decided to go with Arduino Uno and sensor LM35. Idk on the other components. I already have a 12 watt Led light.

Nitrate/Nitrite levels aren't needed, but temperature monitoring is most important. Any other suggestions?

You need to look for a waterproof sensor that can be submerged in water. What does your lighting look like? Are these led strips? Power supply from 12V? Write when you illuminate the aquarium and when it should be off.

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So far I'll be using

  • A thermometer
  • Bluetooth module
  • Arduino Uno Kit
  • Relay switch
  • Wifi router? (when I'm out of Bluetooth range?)

I will be using for the UI @Taifun 's Notification extension, @Patryk_F (your) version of the circular slider, and @Kumaraswamy's new wifi extension.

Will I need any other arduino components? I will do more research today after school...

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This wifi extension is of no use if you want to control something remotely. WiFi direct works only in the local network, you need to have coverage of your home wifi. You have to look for something else, I recommend MQTT.

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What does your lighting look like? Are these led strips? Power supply from 12V? Write when you illuminate the aquarium and when it should be off.

Yes. It is a led light strip for the Liquidy Split Aquarium. I turn the light on @ 7:00 AM and off @ 7:00 pm. I'll get the specs.

Okay, I'll use that. Funnily enough, the example on their page is for a thermometer

If you want wifi I recommend ESP32 over arduino uno. Then you can give up bluetooth and control everything via wifi. Esp32 can be programmed in an arduino environment. The price of the device is similar.

A real-time clock can be used to make the esp32 automatically turn the light on and off at a preset time.

The app would be used to:

  • view the current temperature and correct it,
  • set the time to switch the light on and off,
  • manually switch on and off light and adjust the brightness

Here are the specs

  • Heater- Aqueon Flat 7.5 watt Heater- Model 100101230
    • 120 volts
    • 60 Hertz
    • DC
    • Double pronged-
  • Light- 2 Led diodes (flat)
    • .75 watts
    • 12 volt
    • DC

Okay @Patryk_F, I did some research online on the Esp32 modules. I’ll use ‘ESP32-SOLO-1’.

Components I’ve found-

Now, how do connect the heater and the light to it? The heater and the led’s have à double-pronged plug, but the led also has this↓ which connects it to the switch.

I assume that I’ll also need wires to connect the components together. Right?

Here are specs for the Esp32 Solo 1- here and here.

As for ESP, buy "NodeMCU ESP32". The board with the relay will be useful for controlling the heater. We will control the lighting with PWM through a transistor. Where will you order parts? From China, from Aliexpress? Then I could point you to specific links.

Sorry about the late reply. Network admin made it so that only school Gmail's can sign into anything on the Chromebook: I had to add a password to this account. Still can't access my personal AI2 account. :flushed:

I would like to order the parts on amazon since I already have a gift card on that. Thanks for the help so far.

Found it fast. You can search your way. For this, the housing and power supply would be useful.

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Thanks @Patryk_F. I'll tell you when they get to my house.

Is there any way to make the circular slider 3 layered? One for Time on, time off, and dimming level. And then another one for the desired temperature, max temperature, and min temperature. I was playing around with it a little, but I kept making it glitch a lot.