Hey Zach, it's Dan. Welcome.
You want higher flow rate and bigger media volume (for more good bacteria to grow that breaks down the waste/makes the water clearer). A single AC110 worked well for me on a 55g, or two of them if you're majorly overstocked (aqadvisor.com has a good starting point calculator for figuring this stuff out). Occasionally you could get by with as small as an AC70, but that's not much less money, and you get double the media volume and 60-70% more flow in an AC110. Starting out I only had a Whisper 60, and while nothing died, it got clogged with fish waste pretty often and the tank sometimes got cloudy.
For water change, if you're doing every two weeks, I'd shoot for closer to 50% especially as the fish get bigger, or 25% once a week. But I'll admit I've done the 25% every two weeks before on some tanks and it's been OK. Fish are more resilient than some people give them credit for, which is not an excuse to neglect them, just an observation. The problem with percentages is that it's more dependent on bioload of the fish. 9 1" fish produce a ton less waste than 9 3" fish. So, how much water you have to swap out will change over time.
To save hassle, I'd get a water changer hose if you can. Screws onto the faucet and sure beats hauling buckets. Maybe you already have one.
Another factor that contributes to clear/not-clear water is algae growth. I assume you don't have the tank where it gets direct sunlight? If it's not in direct sunlight, then a better filter will help. But if in direct sunlight, you'll keep having cloudy/green water.
