Earth covered with water in the beginning?

I have heard a monk saying, in the beginning of this kappa Earth was covered with water. And a god or a brahma, I dont remember exactly whom, had put a lotus seed into that water and there grown 5 flowers and they represented the 5 Buddhas (Kakusanda, Konagama, Kashyapa, Gautama, Meithri) in this kappa. But I could not find where in Tripitaka did the lord Buddha say that. So I highly apreciate if someone could help me to find any reference to this. Thanks in advance.