If adding probiotics, the most commonly used strains are lactobacillus acidophilus, animalis and casei. If using the probiotic you can leave the yogurt out for no more than 5 - 6 hours in a warm area once it is all blended together. Personally if you are wanting to culture longer I'd be investing in a yogurt maker for controlling the temperature to ensure you are not growing adverse strains of bacteria or even yeast. Home fermentation is cool but you do need to be a little careful and use your common sense.
Place almonds in a bowl and cover with water. Leave to soak overnight.
The next day drain the almonds and rinse well. Place almonds in a high speed blender with all of the other ingredients and blend till lovely and smooth.
Pour the raspberry & red grape almond yogurt into glass jars and cover with a lids. Place the yogurt in the fridge. The yogurt will keep for 5 days.