The fumes or smell may be objectionable to you , but its ot gonna do
anyhtng to a tank that is nearby........The smell you smell is no
more than what would be found in a big vat of pickles or
juice.......its acetic acid not harmfull as much as it is
objectionable, and to the tank, not a concern.....Of course moving
tank out of room etc would be better but not a necessity..

Even with a tarp over it, you'll still let the accumulated fumes /
smell out when you remove the tarp, but you would only smell it short
time not the entire duratin of cure.....You could also cover over the
top with a piece of plastic sheeting or large plastic bags and
masking tape to keep in the smell until its fully cured.


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I forgot more about ponds and koi than I'll ever know!