Well,
Couple of questions:
Are you brewing your milk kefir at room temp, or in the fridge? It should be at room temp for the first 12-24 hours, then you can strain out the grains, and store the kefir it produced in the refridgerator for drinking at your leisure.... You should try to keep your grains at room temp, in fresh milk every few days or so, to allow them the best growth and production. ONLY refrigerate them if you are putting them into a 'dormant' stage.
Put the milk grains in about a cup to a cup and a half of milk, and let it sit on the counter top for 2-3 days for the first go round. The culture will eventually get it all converted and this will allow it 'undisturbed' time to adjust to it's new surroundings.
It might go through an 'alcoholy' stage, but usually not if allowed to ferment at room temp, and should be smelling nice and 'buttermilky' soon! Sometimes I just cover my dairy kefir jar with a cloth, to allow 'fermentation' smells to offgass, and it's a lighter smell then also.
Also, Kombucha SCOBYs need air circulation, ergo, the suggestion to cover the top of the wide mouth container with one layer of woven cloth or other air permeable material. The air is just as important to a good brew, as the tea/sugar is to feeding the SCOBY. Just so you know. The microwave will not give it fresh air and it might eventually have problems.
So maybe leave the door open a bit?
The water kefir sounds like it's ok. You will want to make sure it's got a sufficient mineral content (via Rapadura/succanant/molasses) and maybe a favorite organic fruit to help feed it to get it going...as it should start bubbling pretty good by the second day. In some cases, with starting off with new grains, you need to let it sit for 3 days. The Water Kefir could actually be in a 'closed' container and sitting in the microwave, as it doesn't need air like the Kombucha does.
The fermentation process, onces well established in your brews, will definitely allow the sugars to be 'mostly' used up, depending on the brew and initial sugar input. The brews need enough sugar to do their thing, and then you just need to time how long before it's not sweet tasting anymore, yet still drinkable and tasty to you!
The cultures themselves will be beneficial to a diabetic, and the sugars will be simple *glucose* by the end of the ferment process, if any are left.
Ok, so hope that helps you with sorting it all out. Starting three cultures all at once is a big task, but well worth it! Glad you got them all going!
Cheers!
