My first swimming pool maintenance experience was back in 2013 when I worked as a superintendent. It was a small, outdoor pool right under the old trees. That pool required at least couple hours to prepare it for opening. Chemical balance was hard to maintain, so after I switched jobs, old tenants say, the pool turned dark green on the third day and city health inspector shut it down for a week.
Now I am a Resident Manager in another building, where the pool is indoors. The indoor pool is very easy to maintain after the outdoor pool. The chemical balance doesn't change much and there are barely 10 people per day using it. Before me, they had way too much chlorine and PH too high. But since I took over, the water looks very welcoming and crystal clear!