According to Scriptural law, what is the minimum requirement for a valid mikveh?
Halacha 1 states that Scripturally, any gathered water — as implied by 'a gathering of waters' — is valid provided it is enough to cover a person's body, without any requirement of 40 se'ah.
Question 2
A mikveh contains 35 se'ah of valid water and 3 lugin of drawn water fall in. What is the status?
Halacha 2 establishes that 3 lugin of drawn water falling into a mikveh with less than 40 se'ah of valid water disqualifies the entire mikveh by Rabbinic decree.
Question 3
Barrels were placed on a roof to dry. Rain fell unexpectedly and filled them. The owner breaks the barrels and uses the water for a mikveh. Is this water acceptable?
Halacha 3 states that barrels placed out to dry that were filled by unexpected rain may be broken or overturned, and the water is acceptable even during rainy season.
Question 4
Three lugin of drawn water are poured onto the ground outside a mikveh and flow into it along the ground. Does this disqualify the mikveh?
Halacha 8 rules that drawn water disqualifies a mikveh only when it falls from a container; if it flows on the ground and enters the mikveh, it does not disqualify.
Question 5
A mikveh has exactly 40 se'ah. One se'ah of drawn water is added, then one se'ah is removed. Is the mikveh still valid?
Halacha 7 states that when a mikveh already has 40 se'ah and one adds then removes a se'ah of drawn water, the mikveh remains valid.