No he has always been in r/o water. What makes it stable? Marble motoroAre you adding anything back to the RO? Straight RO isn't stable at all..... Very prone to PH crashes.
Was it kept in normal tap/well water before? IF trying to transition a ray already in poor health from tap to RO then that could be the problem right there.....
What kind of ray is it? Not all grow fast......
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