I've kept freshwater tanks for years now and I would like to start a low tech marine aquarium. I would like to have some live rock, snails, hermit crabs, maybe some low light coral polyps and other small inverts, a damsel fish or two. I plan on running the tank with a canister filter(up to 30 gal I believe), sufficient heater, and 15W fluorescent bulb. My plan is to keep a simple tank without the really expensive marine critters and equipment. Along with regular water changes and parameter testing, will this suffice to maintain a healthy aquarium?