Long post, and a pic!
I am interested in your box and waterpipe configuration. I had tried to make yogurt from milk, and it was an abysmal failure, and I know it was a problem with ambient air temperature. I keep my house fairly cool (58-60 degrees F). Any chance you would be able to put up a picture?
As requested, I've attached a picture of my insulated box and waterpipe configuration. It should show at the end of my post.
This is on a shelf above our hot water cylinder, in a cupboard - we call it a "hot water cupboard" here. It's in a utility room that doesn't have heating so I use up to 4 layers of polyfleece as extra insulation in the winter. (It's wintertime here now.)
I manage to control the temperature through the year by adding or taking away layers of the polyfleece.
I used the cardboard box and the polystyrene that a slowcooker came packaged in and fitted it around the pipes. It's not perfect but it seems to get the job done. The piece on the right of the pic (with a pinkish tinge) is separate and it fits into the front of the box before the blankets are pulled right around and the cupboard door is shut to keep everything tight.
The polystyrene started getting a bit battered around from my pushing in a hot water bottle to bring up the temperature for yogurt-making, so we recently covered most of it in a strong clear tape.
To get an idea of size, the jar pictured in the box holds 1 litre. I keep a thermometer in there too.
Here's a bit more about the recipes I use:
For yogurt I heat 1 litre of milk (I use full-fat, organic, pasteurised milk, not homogenised) to 180 degrees - just below a simmer - then I cool it to body temperature before stirring in a couple of heaped TBSPs commercial organic yogurt, and 1/2 tsp probiotic powder (that's definitely optional).
I pour the mix into a 1 litre jar and set it in my insulated box which I keep between 95 and 110 degrees for 24 to 30 hours. The temperature is important.
If there are big demands on our hot water supply then the pipe and the box cool a bit, so I need to keep a close eye on things for that 24+ hours. In the cooler months I have to pop a hot water bottle in the box 2 - 3 times in 24 hours to keep the temperature warm enough. Now that it's winter I even have to get up at 3am
to fill the hot water bottle. I don't really mind doing that but If I had to do it more than once a week I'd probably invest in an actual yogurt maker!
The yogurt takes on the exact flavour and very similar consistency of the starter - quite amazing. I'm sure
if you follow that recipe, even if you only ferment the yogurt for say 8 hours you will have really good results.
I drip it overnight in the fridge through a very fine mesh that's typically used for screen-printing which I set into a sieve. I know others use coffee filters successfully.
The yogurt gets very nicely thick, and I end up with 300mls or so of whey. The whey is clear apart from a little bit of white cloudy stuff which settles at the bottom of the jar. It doesn't seem to affect my ferments.
As well as Sandor's basic red and green cabbage sauerkraut recipe I regularly use Sally Fallon's carrot and ginger lacto-ferment recipe which is detailed really nicely on this blog:
By the way, the ginger is just for flavour, but it's not compulsory. My youngest child much prefers just carrot. :Retro smile:
I also ferment beets, red onion and caraway seeds (plus salt to inhibit the wrong type of bacteria) using either whey or sauerkraut juice as a starter.
When making fermented vegetables I don't let the temperature in the box get over 75 degrees. I often have 2 jars going at a time. The lacto-ferments stay in the cupboard 3 - 4 days and "regular" ferments generally about 10 days (but sometimes it takes longer - up to 3 weeks in winter) before I transfer them to the refrigerator.
I find it feels very empowering making my own probiotic foods, especially as I have some control over the strains of probiotic. And I know they're live and potent!
Good luck. If you need more info I'm happy to help.