5 Gallon Saltwater Cube

[mazamotuck]

I've had my share of saltwater tanks within the last 5-6 years but recently I picked up a small 5 gallon reef tank from a friend who wasn't really into fish. I've heard these can be an extremely difficult to keep successful due to the small amount of water.
Right now, I've had it set up for about 9 days now with just sand, one small live rock, and some actual saltwater purchased from my local fish store. I've tested the water and show no problems right now. My goal is to give it 14 days then take the next step by possibly purchasing some sort of live stock but I don't want to jump the gun too early here.
I'm here just looking for advice before moving forward with this tank in making sure I take the appropriate procedures. Thank you in advance for any advice!

 

[flydiver]

Yes, nano tanks are quite the challenge because chemistry changes are almost never slight, so keeping an eye on your water is key.

 

[sweatervest13]

One of the biggest challenges for a pico tank is the live stock that can fit and thrive in that small of a tank. You could probably get away with a fire fish or a clown goby, or something similar to those fish.

 

[snakeblitz33]

You won't want a clown goby - they let too much food pass by them and they hardly eat much.
You might want a pair of pico clowns or a pair of firefish gobies... or something weird like a blue gudgeon. Nothing wrong with a couple of hardy little damsels either. Check out all the different types of chromis out there for sale. Small cardinals also probably shouldn't be passed by.
Are you wanting a fish only tank, or are you wanting a reef? What are your goals for this aquarium?