My pool has what I'm assuming is one main drain (white plastic cover with concentric grates) in the middle of the deep end; excuse my ingnorance, but what is the purpose of this?
Although this question popped into my head last year (1st pool season), never had a problem with the drain, so the need to have this question answered wasn't pressing; however, while brushing my pool earlier tonight, whenever I brushed near the drain and surge of water whooshed by it, a bit of debris (algae? soggy leaves? same thing?) would come out of the drain. So I guess my second question is...what the heck's happening? and how do I get it to stop?