Hi, first time post.
I have an in ground pool that we had re-diamondbrited in 2013. The pool has a main drain in the deep end and a skimmer also in the deep end. Currently the main drain is non-operational and only the skimmer operates. The water is well maintained and in excellent shape, chemicals are in range and color is nice. I brought in someone to dive down and look at the main drain. He said that the main drain is plugged with diamondbrite and some cement. He told me that there are two good possibilities, either the people resurfacing were sloppy and plugged it by mistake, or that there is a leak and they plugged the drain instead of spending a lot of money to fix it. He said he can open it up and to see if there is a leak if I wanted to.
My question is, is there any negative effect on the pool and the water quality to run only the skimmer and the leave the main drain off. I have a little one and I want to make sure that the water is safe and healthy for him to swim in, free of bacteria and impurities.
I'm a novice and would appreciate any advice you may be able to provide.