I feel a skimmer is very important for keeping any large lobster in captivity. tehy love to eat and will make a huge organic mess when they go poo-poo. not to mention that most inverts are sensative to ammonia or nitrite in the water. having a skimmer will save you alot of water changes and alot of headaches. Usually when you see all those lobsters in the tank at the grocery store you need to keep in mind 2 things. A) they dont ever feed them ( which you will to keep him/her alive ) B) Marineland makes those filters for most of those lobtser tanks and they are very well designed to do what they do. my suggestion would be to use a skimmer and live rock with lots of water circulation and really the type of sand doesnt matter since the lobster is going to shovel it all over the tank anyway. which means less work for you providing that you have some mechanical filter to pull out the particulates from the water, however i would use something thats not really fine as it will make your tank cloudy most of the time from the lobster. chillers are quite exspensive and requires some good thought as to what type to purchase, alot of it depends on what size tank, the room temperature and how many degrees you need to drop the tank temp down to. since these lobsters are total cold water.. you are gonna need a big chiller.
