Arduino project for aquarium

Hello Folks,

I am thinking to start a new project for aquarium, I know what some people will say, why this guy does not copy from a google site? :smiley:

At first, I believe that just copying is not a creation and I would like to create something in a low cost project.

Second one motive, I would like to create a proactive monitor to change parameters, send messages when it happens and show water parameters (this last, as the most os projects I saw).

Normally to monitoring an aquarium some parameters are necessary, like:

Themperature
PH
Ammonia
KH (water hardness)
Calcium concentration
Salinity (Reefs case)
Presence of metals and others (Mg, PO4, NH3, NO2)
CO2 (Fresh water case)

I would like to ask your help to create an Arduino project to meter all those above and create a proactive mechanism to change parameter based on programing. For example, If the temperature rises more than 26ºC (78,8ºF) the project could turn on chiller until themperature decrease to 26ºC. For chemical it will spend more research because depends of some calculations.

Could you guide me informing which Arduino parts I need to purchase to complete my project? There are these sensors?

Many thanks in advance!

Best Regards,
Wagner

I would start by doing a Google search for each type of sensor you desire:

aquarium Ph sensor Arduino
aquarium water hardness sensor Arduino
aquarium Calcium concentration sensor Arduino
.
.
.

For each type of sensor you need to find a vendor and instructions for connecting the sensor to an Arduino. For example it won't help much to find a sensor that hooks to a PC through a USB port. Once you know how to connect all of your sensors you can check to see if the Arduino UNO has enough I/O pins or if you need to use the Arduino MEGA 2560.

Hello John, I've started with UNO and my first test I used a sensor LM35 and at this moment I could get temp from water and turn on or turn off based on temp meter.

Thanks for your help, I will learn a little more to use all them sensors on Arduino, maybe UNO is enough.

wchagas:
Normally to monitoring an aquarium some parameters are necessary, like:

Themperature
PH
Ammonia
KH (water hardness)
Calcium concentration
Salinity (Reefs case)
Presence of metals and others (Mg, PO4, NH3, NO2)
CO2 (Fresh water case)

A few of these aren't going to happen. For instance there is no way to monitor KH other than doing the titrations. I guess you could build an autotitrator, but that would be a really big project. But you're not going to get any probe or sensor for it as it is not something that can be measured by electrochemistry.

Calcium is similar, there are ISE probes for calcium, but they are more than a thousand dollars and might last a day in a fish tank. So unless you want to spend a couple of grand a day for continuous monitoring you'll need to run those by hand as well.

Ammonia is similar to calcium. There are probes for it, but they are not appropriate for continuous monitoring in an environment like an aquarium. Besides, if your tank is cycling nitrogen properly it should always be at zero. It isn't very useful to measure unless there is a problem.

The same is the case for the other metals and things you listed. There just isn't available technology to measure those in the way you will want. You're going to have to stick with test kits for those.

I'm not sure if there is anything to measure CO2 levels in solution. So you'll have to do y our own research on that one. But I doubt you're going to find anything that is appropriate for this sort of project that doesn't cost an arm and a leg.

So that leaves you with the ones that aquarium monitors normally watch, pH, temperature, and salinity (via conductivity).

Go have a look at the Reef Angel controller. I haven't messed with it much, but it is all open source so you should be able to get a ton of ideas from it.

Gases can be continuously measured via light absorbance. It is possible but I am not sure if it can be DIY with "normal components". Also I don't know if it can be used in water for substances you are interested in and in small amounts.

I wonder how hard it would be to make your own mass spectrometer.

johnwasser:
I wonder how hard it would be to make your own mass spectrometer.

Here's the trap... :slight_smile:

Just work out the RF so you can scan the stuff back out and a detector of some sort and you're all set.

(PS. I build and service MS systems for Thermo Scientific in my regular job.)

I take it most of these tests that can only be done manually are just chemical indication tests?

If so, maybe you could have pumps to take sample water and add the correct amount of indicator for each test

trojanhawrs:
I take it most of these tests that can only be done manually are just chemical indication tests?

If so, maybe you could have pumps to take sample water and add the correct amount of indicator for each test

That might work. The Nutrafin Aquarium Test Kit has reagents for:
Ammonia (NH3/4);
Nitrite (NO2);
Nitrate (NO3);
pH (low range & high range kits);
Carbonate Hardness (KH);
General Hardness (GH);
Iron (Fe);
Calcium (Ca);
Phosphate (PO4).

It's only about $90/kit

It depends on what type of tank you're keeping as to which type of tests you do. For a seawater tank the calcium, magnesium, and hardness (KH) tests are pretty critical so they are usually done by titration.

Color changing tests for pH are all crap and should be avoided if you really care what the pH is with less than about 1-2 pH units of resolution.

Here's a quick and dirty vis spec using Arduino. Was originally intended for doing colorimetry tests, but needs much optimization. Spectrophotometer in a Shoebox! - Reef Central Online Community