Anybody tried replacing EC sensor with Turbidity sensor in DWC setup?

This would solve some interference issues with pH sensors and can be setup in the exact same way as a generic EC sensor.
I wonder if anyone tried it out?

Can you explain in more detail what you are trying to accomplish?
You can’t measure EC with a turbidity sensor.
Likewise, you can’t measure turbidity with an EC sensor.
They are measuring 2 completely unrelated things.
Turbidity optically measures suspended solid particles in the water (cloudiness).
EC extrapolates how much dissolved solids are in a solution by measuring electrical conductivity.

Example… you have a quart of distilled water, you measure it with both an EC and turbidity meter.
They both read about “zero”.

You pour a half cup of salt into the water and mix it until completely dissolved and take another measurement.
This time you get a much higher EC reading, while still getting a “zero” reading on the turbidity sensor.

How is the EC sensor “interfering” with the pH sensor?
When EC changes, it is likely also going to cause a change in pH, but not necessarily vice-versa.

I´m aware it´s not the same thing they are measuring.
However, if I mix my water with fertilizer it will have a value not zero.
Which means that as long as I get the same value the next time I mix my water, the ppm will also be around the same as the first mix.
In reality I dont care what the value is, it´ll be converted to whatever number I want either way.
I don´t know how it´ll behave when the plant starts eating, but my assumption is that the plant eats some of the particles in the water, thereby also reducing the reading.

No, that is absolutely not the case.
Like I said, there is no definitive correlation between turbidity (cloudiness) and dissolved solids.
Turbidity totally depends on what kind of undissolved solids are suspended (not dissolved) in the water.
Turbidity can also change drastically with temperature, or algae or bacterial blooms.
If you wanted to extrapolate some kind of a correlation, you would need to take readings with both an EC and turbidity sensor.
If you try to measure EC with a turbidity sensor, you are going to end up with a completely arbitrary number that has no real significance (or accuracy) to what you are actually trying to measure.

You still haven’t answered the question as to why you would even want to try this?
Why do you think your EC sensor is causing “interference issues” with your pH sensor?

This is true to a certain extent. The plant will only remove some of the dissolved solids as it uptakes water into the roots and distributes it to the plant. (plants can not absorb visible particles in the water, they are too large for the plant to uptake, so again, turbidity is actually something you don’t want in your res). Then the plant transpires the excess water through it’s leaves. A plant always uptakes more water than nutrients, thus there is always more transpiration/evaporation happening in your reservoir than there is a loss of dissolved solids. This means that EC is going to go up in almost all cases. Only a little bit of evaporation can cause EC levels to rise drastically and easily reach toxic levels for your plants, especially if you are using a maximum feeding ratio. The only way to prevent this is to have an automatic filler on your reservoir that keeps your tank topped off with fresh water at all times.

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