Clear water is a filter doing its job, not a lucky chemical reading. On a fibreglass pool you have options, and the best one is the one you will actually look after.
Cartridge filters are common on residential installs. They trap fine debris and you rinse the cartridge rather than backwashing thousands of litres. Sand filters are simple and familiar. Glass media can improve on sand with finer filtration. DE filters polish the water to a very fine level but they take more care. Your water quality, garden debris and how much space you have on the equipment pad all matter.
We size the filter to the pool, not the other way around. If you have a lot of trees, or you are near the coast with fine dust, say so at the consult. Meredith’s team will set the plumbing so the filter is easy to reach. A filter you cannot service will not stay sparkling.