White spots occasionally in the cage are normal. This happens because
cavies only keep the calcium they need and their bodies expel the rest through their urine.
One thing all
cavy owners need to do when seeing these spots is to feel them when they are dry and see if they feel smooth or a bit gritty. Smooth spots are perfectly normal. Gritty feeling spots can indicate bladder sludge and then a modification to the diet is needed. Bladder sludge is a precursor to bladder stones.
If you have a
cavy with gritty feeling white spots, then cut down significantly on calcium enriched veggies. If you need help with what foods are high in calcium, please see the sticky thread-
http://www.guineapigcages.com/forum/...arts-info.html