Aqua Clear Filter Q's

[Kabong]

The sponge to catch stuff

The carbon to polish the water. (As long as you want the water polished that it)

Ammo-rid to help lower ammonia levels. (Alright for an emergency, But shouldnt you really just do a water change or figure out whats causing the problem.)

Zeo-carb is 1/2 & 1/2 of carbon and ammo rid.

Theres nothing wrong with haveing all on hand, But i wouldnt run them all at same time. I myself run a sponge on my fresh tank's and will only use the others if there is a need.