I agree with the light comment... and it goes beyond that.
Buy the right equipment the first time. Research your purchases, and buy equipment that might be more expensive at first, but that performs well and lasts long. Saving $100 on that cheapo skimmer might sound good at first, but it's a waste when you throw it out a year later to buy something that meets your expectations. Invest in equipment, don't just piss money away.
The DIY point is also good.. learn to build things yourself. Stands, canopies, and sumps are within the means most people with basic tools to accomplish. Even if you have to buy tools, you can use tools for other things besides your tank. You'll learn more in the process too. If you don't try to do things yourself, you'll never know if you can.
- When buying lighting, consider the operational costs versus the up front. Compact fluorescent fixtures are cheap, but the lamps have to be replaced so often, you're far better off to invest in that T5, you'll be way ahead in a couple years.
- GO SLOW. Rushing to introduce livestock causes premature deaths that discourage, frustrate, and drive up costs.
- Mix your own seawater, and if you have any sort of sizable tank, invest in RODI rather than buying water. Consider the time and gas to keep having to go out to get water.
- Don't invest in gimmicky equipment, chemicals, or other nonsense. Good husbandry, light stocking, and patience are far cheaper, safer, and more rewarding than going overboard and having to reach for miracle cures like algae chemicals, UV units, the list goes on.
- Buy bulk chemicals rather than bottled stuff. Pickling lime that you can get at the grocery store for a couple bucks is the same stuff you pay $20 for half as much on in jars labeled "Kalkwasser mix." Buy ferric oxide rather than phosban. Buy epson salts instead of magnesium supplements. Spend the money you are spending on lofty additives on good test kits instead.
