We don't run our RO unit very often. We fill up a 200 litre butt and use it as we need to. It stays there for weeks/months. It is a sealed container so nothing gets in. We also make sure the membrane in the RO unit doesn't dry out in between it running.
thats the best way, just fill up a large container and have a larger container for the waste water which cant then be used in a freshwater tank, like a lightly stocked heavily planted tank if its got very high nitrates and phosphates and then into another freshwater tank via water changes
There are no experts, mearly beginners who know more than others.
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