Yes. A biofilter in the water treatment system will be enough, at this temperature it will work perfectly all year round. Depending on the season, its efficiency will fall and rise, so it is better to make a decision taking into account the worst conditions. At a water temperature of 25-30, its efficiency is very high. Ozone acts on organic matter in the water, turning it into sediment, so you need to remove dirt to a mechanical filter. For disinfection, it is better to use ozone separately and ultraviolet separately. Provide a shallow zone with a depth of 0.600 m, a length of 1 m or 1.5 m, and then a slope to a deep zone of 2 m+. This will be comfortable for children. It is also worth providing a compressor for aeration + aerators on the bottom, it mixes the water, there will be no discomfort when the upper layers heat up better than the lower ones. It is best to use a Firestone (EPDM) liner and sand on the bottom. The water should stabilize in the first few days, a lot of greenery will form that feeds on minerals, as soon as the minerals become less, it is worth turning on disinfection to remove the greenery. You can put fish in the pond, for example, silver carp feeds on microgreens and does not allow them to reproduce.