On: Sunlight through glass does not provide Vitamin D

[rapsey]

I dont understand the question. The difference between using every other day or every two days?

[Vinnl → rapsey]

Using every other day = use one day, then not use it the day after.

Using once every two days = use one day, then not use it the day after.

Perhaps you meant "once every three days", i.e. use it one day, then not use it for two days?

[rapsey → Vinnl]

Yes I meant every three days