The new vet seems to know her stuff. She said "simple is best" when it comes to axies.
I've reached the conculsion that filters are basically useless for axies because filters only work best with good water movement. Axies, of course, hate water movement. Filters only serve to decrease the frequency of water changes, but in the case of axies they pose a potential hazard because bad bacteria can sometimes overtake even a properly cycled tank. Again, because the filter can't do its job if the water isn't moving fast enough. Basically, if you want an axolotl, you have to do lots of water changes, filter or no filter. One simple hide for an axie is ok, but not essential. They won't die without one. And it has to be cleaned all the time, even with a filter in the tank. "All the time" means "with every water change." Eno had three hides and never used any of them, BTW, so I guess he didn't read the websites that said axies need hides. LOL
One person here made the comment, "...did you not think to move the ornaments and clean underneath them?" This is insulting but not helpful. But to address this comment, yes, I did think of it. But "experts" said such cleanings only have to be done monthly if you are doing regular weekly water changes of 20~30%. I was doing DAILY water changes of 40~50% or more. Eno got sick within two weeks of my adding the decorations. Many self-proclaimed axolotl experts, and even many vets, are not fully experienced with axies, as we found out.
The new vet put Eno on anti-biotics. We hope they do the trick. Salt baths, incidentally, are NEVER good for axies, contrary to popular wisdom--even on this site. I'm told it has to do with osmotic pressure. Since I'm not a vet, I won't pretend to fully understand, but her explanation essentially said that axies are not fish so they should not be treated as fish. When I mentioned "experts" who treat axies' fungal infections with salt baths, she nodded and said many vets make that same mistake, but it's the wrong treatment. It will kill the fungus, sure, but it also puts undue stress on the axies and damages their gills, even if you only put them in for 10 minutes. They heal because axies have amazing healing powers, but you are still injuring them unnecessarily. So I asked, "What do you do for fungal infections on axolotls." She laughed and said, "We use an anti-fungal medication." Duh! LOL
These forums are great for discussion, but I really learned my lesson. Don't listen to people on the Internet, and trust your instincts--even if a vet or doctor tells you otherwise. I had a feeling that the salt bath was a bad idea, but figured "I'm not a vet. Who am I to argue?" That was wrong.
Thank you all for your help and advice. Best wishes to all of you and your beloved pets. Thank you all for your positive thoughts, prayers, vibes, etc., for Eno. We both sincerely appreciate them.