Recently we decided to invest in a second hand marine saltwater aquarium and I've been staring at it every night for the past few nights. The tank is the Aqua-medic Blenny and it's got two clownfish, a coral banded shrimp, a number of snails, a hermit crab and a small collection of corals. I've been doing a lot of reading and research on how to maintain it but I was just wondering if anyone has any experience on what are the basics and some common mistakes that a lot of people make? I'd also like to know if anyone has any suggestions on websites, and good aquarium shops in Melbourne that they frequently visit for cheaper marine supplies. I've signed up to forums already but I thought that the hardcore ozbargainers might visit here more than those forums.
Thanks in advance.
The smaller the tank, the more difficult it is to keep marine fish, and even more so live corals, which need high quality water parameters to survive. Your aquarium (at 21L) is quite small by reef aquarium standards.
Even though your aquarium is designed as a reef aquarium and comes with appropriate filtration, if I were you I would try to trade in your corals at a local fish shop for some store credit, and focus on keeping the fish alive initially. If your clowns are Ocellaris Clowns (ie Nemo) they are likely captive bred and so should be fairly hardy. But you should introduce new fish slowly and carefully given the size of your tank. A lot of species won't be able to be kept in such a small space. Once your tank is established and you are more confident in maintaining it you could look to add some low maintenance corals and go from there.
Otherwise, do regular water changes. I collect my aquarium water from the ocean in 10L water jugs bought for $4 from Woolworths, which makes it much cheaper than using salt mixes or buying saltwater directly from an aquarium store.
Otherwise I am in Sydney so can't help re Melbourne stores.
Anyways, enjoy your aquarium. I love mine but it does take a fair bit of maintenance, and is by no means a cheap hobby!