You can use almost any kind of container:
Coolers, Tupperware tubs, deepfreezers, etc. but the importatnt thing is to keep the water cool and clean.
I personally use a working deep freezer with a temp control to cycle the freezer power when desired temp is reached.
I made my filter out of 3-4" PCV (cannister type) that fits all 3 types of filtration material. A Supreme Mag pump to pump the water through it and plain old PVC with holes in it for the spray bar. A smaller Rainbow Quiet One pump for extra circulation and a couple of air sticks glued to the bottom hooked up to a common air pump for aquariums for extra oxygen.