Hello Swen and welcome to Pond Boss. I have used Cutrine in the past with no apparent detrimental effect to anything other than the Elodea that I was treating. But this is just anecdotal evidence, lets get some expert feedback.

JHAP
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"My mind is a raging torrent, flooded with rivulets of thought cascading into a waterfall of creative alternatives."
...Hedley Lamarr (that's Hedley not Hedy)