Fish Suggestion

[Richer]

I love sand dwelling fish, but I cannot keep them because my main display tank is a BB tank, so I am now in the planning process of plumbing up another tank into my current setup. So far, I plan on putting a 4-5 inch sand bed in a 15 gallon tank (24"x12"x12"), and plant it with macro algae and move my current refugium setup out of my sump and into this tank. Tank will be lit with a 55watt PC setup, and will have a cover (glass, or eggcrate at the least).

Of the choices in the poll, which would you pick and why?

Thanks!
-Rich