7. I measure parameters more often than @Paul B - but not that often -
I collected some water yesterday and tested the salinity. It was so low I could have probably kept kissing gourami's in there so I added salt. Then I tested the water in my tank and the salinity was so low that I probably could have kept Discus and goldfish with those kissing gourami's.
I didn't realize but the way I have my skimmer set up now, the water from the effluent goes right into a drain so I don't know how much water is lost. It used to go into a bucket and I would replace that water with seawater.
The skimmer must have been going nuts for a few weeks and dumping out the water which is automatically replaced by fresh water. I am going to have to work on that. Or start buying Kissing Gourami's..
PS I will look for the rest of that research about the kidneys processing chemicals from parasites. Right now, going out to a nice dinner by the sea. The very cold sea.