[shrimp? fish? CRABS?!?]

Purchased an FX6 for a discus tank,

so would I need to buy foam for the intake?

 

[deeda]

You shouldn't need to for discus. If you choose to add a pre-filter or sponge to an Fx6 filter intake strainer, make sure it has large pores and check it daily as they get clogged fast and can impact the filter operation by reducing the amount of water the filter needs to operate properly.