There are many ways to achieve what you want to do. Paludariums are a bit more tricky than a regular viv, due to the extra equipment involved.
Filtration is obviously a big concern, and your design is going to really decide what kind of filtration you use. It can be as simple as a whisper fountain filter (I think it's the 10i or something like that), a canister, a submersible, or even as basic as a pump surrounded by filter pads. They all have advantages and disadvantages. Again, your design will pretty much dictate which filter you decide on.
Cleaning: in a living Palu, you are going to want a cleaning crew. Isopods and springtails are crucial for this. They are small, tiny bugs that will help break down waste. Of course, you will still have to spot clean larger pieces of waste, but the bugs will help with every thing else.
Accessing your filtration, again, depends on your design. I cannot stress enough how you should have at least a basic design to work with. Plan, plan, plan. Plan for everything imaginable. Where will the water flow? Keep in mind that water is, for the most part, uncontrollable. Are there any gaps which could cause problems? How do I access equipment in case of failure? Ect, ect.
Basically, start with a design, and then work from there
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