If milk kefir keeps separating most f the time the means that milk grains to milk ratio is too high. Or the temperature of fermentation is too high. Try removing some grains or add more milk to...

Milk kefir over fermented when kefir grains finished consumption of all lactose in milk. You can see liquid whey separates from a curdled thick part.  Over fermented milk kefir develop sour...

Milk kefir not fizzy is a good sign indicating your grains are not too yeasty and fermentation time was right.  To make milk kefir fizzy ferment longer time under tight closer lid. Another...

The reason for milk kefir not thickening could be either a low ratio of kefir grains to milk. Or milk used for fermentation has a too low content of fat.  If you try a different type of milk...