I would never ever do this. But I spawn plecos which come from rivers with pristine water (mostly the Rio Xingu in Brazil). The fish I spawn I have paid anywhere from $270 to $1,000 per fish to acquire because of how rare they are and how difficult they are to acquire let alone as being proven breeders. Almost all of the fish which have had spawn in my tanks for me have been egg layers since I stopped keeping live bearer almost 20 years ago.
Most of the fish I have had reproduce in my tanks create a limited number of eggs which is one of the reasons they are so expensive. I can say that triggering them can require doing a dry/rainy season simulation. But this does not mean the water is dirty, it means it is harder and often a bit higher in pH in the dry season. Their fry need very clean water.
Besides ignoring father fish, you have to forgive him as he is apparently old and senile and probably no longer remembers from which end a fish eats.
I have no problem drinking the same water water I put into tank after a water changes or for a new tank start up. The water I take out goes one of two places, out a window or into a toilet. Once in a while I will water the two potted plants we have inside the house. We have had them for a several of decades.
I almost never use Youtube as a source of information for fish unless I know the person who made the vid.
