How to decide the size of the replacement of the filter and pump for inground pool?

I have a 18X36 standard pool filter and motor 1HP / pump with an FS of 1.5, and want to replace my filter pump sand and my present as well. I've had nothing but problems with my filter and the pressure I drop my interview, I'm sure it's because of my stay on top of it, but the neighbors have the sand and not those problems, the more they have automatic indoor pool so if you do not open the pool in general insnt that dirty. I received several estimates, each with different models, I would like to know which model I recommend anything that narrows my options so you can make that decision with a better information. I just want to make sure I'm doing the right size and the series and the brand is best for our pool, and make the most of every dollar. Thank you, I Thanks for your help and support in this regard.

Too bad that had problems with ED usually a good choice, I recommend cartridge filters, but I recommend you for a 520sqft carpool filter. View Pentair pentairpool.com for cleaner and clearer. They also have a large SAN that is called a filter cartridge that is ED as a complement to remove the nuclei for cleaning and not having to go through the exercise of putting a new blade type of filter. Pentair sand if you want too. Check the Triton. For a pump that I would be nothing more than they have since shure that water flows faster but at a more high. Pentair is a speed of variable speed pump with 4 or more than two models, but we do not have a spa that will probably not be interested if Intelliflow has an interesting feature, which is the only pump on the market that save your own life or someone, due to obstruction aspiration. It detects the blockage of the flow and montior turns off immediately, whatever the time of a basket filled with leaves or lock life.

Vinyl liner inground pool with auto cover