http://www.fnzas.org.nz/fishroom/viewtopic.php?t=3725
I used to have a rock pool marine and needed a chiller in summer.
Most fish caught in the sea grow too big for an aquarium but rockfish and triplefins from rockpools look cool.
Mt tank was 3ft x 1ft x 1ft with an AquaClear filter. It had sea anemones, sea cucumber, hermit brab, starfish, brittlestars, chitons, shrimps, a rockfish, triplefins and anything else we could catch in the rockpools. We topped the tank up when required with fresh sea water and gathered sea lettuce for the inhabitants to eat. Luckily we are only 20 minutes from the beach.