If you're in the market for an above ground pool filter pump, there are a few things you'll want to keep in mind. First, decide whether you want a sand, cartridge, or diatomaceous earth (DE) filter. Each has its own pros and cons that should be considered before making a decision. Sand filters are the most affordable option and require the least maintenance, but they can be difficult to backwash and can't trap as small of particles as other types of filters. Cartridge filters are more expensive up front but last longer and are easier to clean than sand filters. They also do a better job of trapping smaller particles. DE filters are the most expensive option, but they offer the best filtration and require less chemicals than other types of filters.
Once you've decided on the type of filter you want, you'll need to choose a pump that's powerful enough to circulate the water through your chosen filter. The size of your pool will play a role in this decision - generally, larger pools require more powerful pumps. You'll also want to consider how often you plan on using your pool when choosing a pump - if you only plan on swimming occasionally, you won't need as powerful of a pump as someone who plans on using their pool daily.
Finally, make sure to read reviews before purchasing an above ground pool filter pump so that you can be confident in your purchase. With so many options available on the market today, it's important to do your research to find the best pump for your needs.