Common Errors: (In no specific order).
1: Lack of Research on the entire hobby by the Keeper
2: No RO. By a Unit, or buy gallons of it from your LFS.
3: Stocking with in-compatable species or species which require specialist care.
4: Dosing with un-neccessary products. Dont add what you dont test for!
5: Patience. Guilty of in-patience myself on occasion, try and relax, and watch the hobby from all aspects.
Top 5 Best Things you Could do:
1: Invest in RO. Water clarity, coral growth and extension...the benefits are huge.
2: Buy atleast 2 recomended, recent books, on the hobby.
3: Research Research Research.
4: Buy quality, buy right, and do things proper the first time rather than spend your life saving to upgrade.
5: Just know what your buying. It saves tanks and lives!
Awsome Top 5 reasons to keep marine: (Sorry, had to add this SH)
1: Bacteria/macro life/plants/algae/inverts....everything you can think of, and thats just on the LR!
2: The Fish!
They are amazing, and occupy hundreds of different niches.
3: Corals! What tank would be complete with out even shrooms or Zoas.
4: The huge diversity of animals you can choose from.
5: The fish/inverts have varying, funny, agrivating, frustrating, and lovable character.