I started off 12 years ago with a nano and up until the last 2 years had a 29G. To echo others, stability is key and is more challenging in a small tank. I also agree that you should do weekly water changes to replenish trace elements and keep Alk/Ca/Mg in proper quantities (unless you are dosing them). This is especially important if you don't have a good protein skimmer running.
A few tips with the water changes:
- Temp and salinity need to be as close to the same as your tank on the new water. Otherwise you will shock your tank and corals.
- Allow salt water to mix for at least 12 hours before using. Use a pump and heater in the mixing container.
- Pour in the water slowly and in the path of a pump to dilute it.
- Use RO/DI water only for changes and top off, even if you have to get it at the LFS. Trust me, it's worth it!
Tips for stability:
- Add a sump for more water volume. More volume = more stable
- Try not to let your temp fluctuate more than 2 degrees in one day.
- Get a decent test kit and test often
- Don't go nuts with supplements. Be conservative and increase slowly
- Add bioload slowly.
- ATO is your best friend in a small tank
General thoughts:
- The amount of money you spend on the equipment is usually inversely proportional to the amount of time you have to spend maintaining
- You will enjoy the hobby more and have more success if you automate key tasks like lighting, ATO, Alk/Ca dosing, and part of daily feeding
- Patience is key!
Just my 2 cents. Hopefully this helps.