Great questions. I've used garlic in a fish sauce to try and approximate a cambodian fish sauce I tried once and fell in love with. It came out pretty well. I love experimenting with flavors once I get a good recipe down. The only draw back is a 6 month investment of time is a lot to gamble on anything too crazy. There are ways to speed up the process using koji (aspergillus oryzae), an edible mold, but that's another whole can of worms.

Most fermentation benefits from steady temps in the mid to low 70s but I don't fret too much about it. I just put it in a closet. I do have a fermentation chamber I've built for more temperamental ferments (beer, tempeh, growing koji spores) but I didn't need it for years. Most ferments are pretty forgiving.

My current fish sauce is in the fridge in a glass condiment bottle who's origin I've long forgotten.

Sorry for the long winded response. I've been drinking and I geek out hard on this stuff. Good luck! Hit me up if you have any more questions.