Disappearing Zucchini?

I thought it was cucumber rind that was especially tough for fish, not zucchini?
 
I weigh down zucchini with lead plant ties (which, I've been told, are not actually lead and are safe).
 
I tried some blanched zuchini in my tank once. The otos never went for it after 8 hours and I had to fish it out and feed it to the dogs. That little bit of rind is too small to even make a dent on your Nitrates.
 
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