Okay, so I’ve been doing some more reading about studies on plants and the temps they like. I’m still trying to contemplate it all. Found lots of good stuff. Some on plants in dirt and some in hydroponic. Couldn’t find much about the differential temperature between roots and leaves though some sources talked about osmosis and capilary action. Some even mentioned some plants absorb water from the air.
But either way it sounds as if a temperature difference is needed for plants to absorb water and grow. I am assuming that this means plants will not grow or grow very slowly if their roots and leaves are at the same temperature. If this is true then in a fog or aero or hydro system it seems critical to keep roots cooler. Though i wonder if warmer would also work if supplimented with more oxygen (CO2?)?
The downside is it is kinda difficult to keep roots cooler in an artificial system though not impossible. I saw some threads on here about root cooling systems.
I’m mostly talking to myself right now.
But a correlation in water systems is that the warmer the temps get the lower the dissolved oxygen gets. In still not certain whether it is actually dissolved CO2 that roots need since plants breath CO2 and exhale oxygen. Most of these articles talk about plants and dissolved oxygen. I kinda suspect they were written wrong. Maybe it’s just easier to test for dissolved oxygen than dissolved CO2. Or maybe my assumption is way off base. But regardless i figure if you have a simple air pump and air stone (then you are sending in both CO2 and oxygen, etc.).
So anyway, it seems that if one is trying to control a simple system like a piezo mister like i was talking about before then it would be best to not only turn it off when the water reaches a certain temp but to also try turning on a cooling fan which should also help circulate air to the roots which may be more important than the heat. I’m thinking the heat doesn’t matter all that much, what matters is if the roots are suffocating and whether there is a temperature differential between roots and leaves to achieve maximum growth potential. It is interesting that plants grow the most at night when it is cool.
I have designed a quick 40mm x 40mm fan adapter for a 5v fan i have lying around that i can hook up to my arduino for just this purpose. I designed the fan adapter in a 3" netpot size so it will fit a 3" hole just like the plants without fussy hole drilling or modding or whatever. I can share the CAD / STL file for anyone who wants to 3d print their own.
I do have an airpump with air stones that i could use too, but i kinda just wanna see how the simple temp probe and fan system works first.
So that’s all my random babbling for now.