/diy/ - Do It Yourself

>>609524
You can do anything in life cheaper as long as your time has no value. good luck

>>609524
>>make it myself cheaper.
MAKING a sensor system involves being able to do electrical engineering. How much of it really depends on how stand-alone you're trying to make this sensor, and what support equipment and tools you have available.

$150 is going to be really difficult to compete with.

If you don't already have some experience with electrical engineering, sensors are probably one of the worst projects to start with and you're not likely to save yourself any money.

The domestic supplied sensors will be more expensive, but will be more documented and have better technical support. This makes it unlikely that you can make a price competitive alternative.

The Chinese ones will be cheaper, but will include little to no documentation and no support. Without a wealth of background experience they would be useless to you.

Ion selective electrodes deteriorate fairly quickly. it would have ongoing costs and you couldnt use it continuously. maybe trigger it to dip into the liquid twice a day to take a reading.
http://creative-technology.net/MAKE.html

>>609718
maybe you could make that spectrometer and calibrate it to trigger a correction when the concentration is too high. I'm not sure how good it would be at qualitative testing.

it might be easier to simply rig premade water to flush the tank every day and dump some water. like have an overflow at the top of the tank that flows into a bucket and blast in an extra 10% of water every day.

>>609721
Ya, that sounds a lot fuckin easier

or realise the nitrate correlates directly with the metabolism of the fish(temperature, light, how much you feed them) keep those constant and their nitrate output should be fairly constant.

>>609731
Sounds like he has a reef set up. If you have live rock, a good protein skimmer and your fish load is not to high, then nitrates will not be a problem. It should be almost self sustining

OP here, thanks guys for all your answers, I am not having any kind of problem with High nitrates, I just want tl be able to monitor it. I have been looking the sensor I told you, and it is using some kind of reactive in order to take all the measurings, so it is kind of tricky... (you have to refill reactive once a month).

I have been reading some documentation about estimating nitrate levels by monitoring absortion of 220nm wavlength UV light by water.

However I couldn't find any 220nm light source (and sensor) online to buy.

Any suggestion?

Overflowing the aquarium with clean water is another project I want to do :)

>>610079
>220nm
well wikipedia says this:
Diamond (235 nm)[65]
Boron nitride (215 nm)[66][67]
Aluminium nitride (AlN) (210 nm)[68]
Aluminium gallium nitride (AlGaN)
Aluminium gallium indium nitride (AlGaInN)—down to 210 nm[69]

any photosensor would work as they're reactive to all light spectrums i assume. could depend on the epoxy they're coated with.

so you need to find an led that doesnt exist in mass production. usually you can find dentistry and medical equipment designed for specific uv spectrums for hardenning epoxies like fillings or cutting. the bulb lifes are like 1000hrs though...

>>610102
>any photosensor would work as they're reactive to all light spectrums i assume. could depend on the epoxy they're coated with.
Not true; a detector's wavelength sensitivity is determined by bandgap just like an emitter.
>so you need to find an led that doesnt exist in mass production.
They exist in mass production. They're incredibly expensive though.

>>610102
>>610299
Yes and the op wants to do this all for under $150. So quit all your faggotry hypothetical shit and just tell him to spend the $150 on the already existing sensors that do all this. Done

OP again,
This is a placer for DIY, right?
Please stop telling me to buy the 150 sensor! I want just to study the viability of doing it myself nd maybe looking foe alternatives that might appear during debate :)

Do you have any links where I could get one of those light sources?

I read a paper that, monitoring 220nm wavelength and also 275nm(where nitrites do not absorve) a rough estimation could be done.

Any other ideas? Maybe the level of nitrites is paired with some other thing that could be detected easier?
Smells, water visible color, faster/slower reaction to temperature... ?

*Nitrates

>>610322
No idea about 220nm, but 275nm LEDs are availlable commercially.
http://www.roithner-laser.com/led_deepuv.html
Same with suitable UV photodiodes.
http://www.roithner-laser.com/pd/pd_uv.html

>>610299
true. turns out all currently available photoresistors cut out around 300nm with far ultraviolet barely even being experimentally available at the moment.

Is the nitrate probe really important ?
I thought nitrite and ammonia is more dangerous to fish ?

In typical freshwater, nitrate level are maintained by water change weekly. So yeah, just automate the water change.

For reef, there's denitrator or something. Not sure if it's worth or not.

>>610335
There are commercially available photodiodes which cover the required range. See >>610330. Even silicon photodiodes with quartz window will see down to 220nm. That said, I'm tempted to assume it would make more sense to use nitrate sensitive dyes and use visible light to read them. With eyes.

>>610347
Monitoring amonia and nitrites would be awesome too. Anyway my tank is now pretty stable (0 nitrites, 0 nitrates). So I would like to monitor the nitrates in order to optimize water changes. I'll look into amonia and nitrites probes to see if they are easier to measure! Thanks!

>>610348
Problem with dying reactives is that automation becomes quite more difficult. Extract some water, put the reactive, wait, check color, bump that water out of the aquarium. With the extra cost of having to be pending of not getting out of reactive ...

>>610359
Immobilize the dye on a plastic base. Wouldn't be a surprise if that $150 instrument was based on that principle. The basic problem here is that you're trying to beat a cheap commercial sensor in price by using methods which are more suitable for expensive lab instruments.

>>610368
More info in how to do this?

They definetively use some kind of plastic card with some reactives.

Can this kind of "solid" reusable reactives be bought easily? I only know the paper strips, but I think they are only valid for one single use

>>610330
>>610348

still doesnt quite make it to the required 220nm

>>609618
I'm so sick of you "your time has no value" crowd. Always condescending to people. Did you ever consider that people enjoy this kind of thing?

>>610999
*clap clap clap*. Totally agree

>>610999
Hey numbnuts, then the op should have left the "do it for cheaper part" out. He did not imply this was his fucking hobby.

>>611058
go back to >>>/b/