Deck Maintenance

I have spent the last two days cleaning the green off my deck.  How gross.  I have it almost where I need it to stain it but I have to get the algae completely off.  I want my husband to check all the nails, screws, and the lag screws he and his dad used when they built it to make sure all is sound (should be since it is only a few years old but seeing how the deck is raised halfway up my house...better to be safe than sorry).

My mother-in-law says not to use stain because it gets slippery.  If not stain, then what?