Hello,
I already had a very similar problem and it took me a long time to understand what it was.
The pH of the water changed very quickly (2 or 3 days) and a kind of algae appeared in the hydro-irrigation tubes.
I finally found the cause and solved my problem. The cause was “The light cannot touch the water that circulates inside the irrigation tubes” !!!!
You would just have to change the tubes, to black tubes instead of transparent ones.
I hope I helped you
sorry if my english is bad. :)
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