Someone gave me a pond liner for a pond between 2500 and 3000 gallons. The hole they had was approximately 10 x 10 x 3.5. They were using a skimmer to filter it and suggested I do. I was wondering if that's necessary. I'd rather use a pressurized pond filter with uv. Do I still need a skimmer if I use one of those? Anyone have suggestions on what they think the best way to filter is? Any specific models I could look at I'd appreciate as well. Thanks.