Suitable Media For Built-in Filter? Options

[shimark]

Hi All,

I am planning to buy a 3ft tank with built-in filter compartment. Have decided to stop using canister filter due to a few bad experience with leakages. Hope to have a filter system thats need as few maintenance as possible due to busy schedule. Thinking of using the following filter media:-

1. First layer (from top) - wool
2. Second layer - Bacteria house (for the top wet dry part)
3. Third layer - BioHome
4. Fourth layer - Plastic green mat
5. Pump compartment - oyster shell

Would appreciate any comment or suggestion to improve the above system.

Thanks