What is the best footprint of a tank for a start of five L. Multis? I am setting this up in my LR and so I am hampered for room. Could I use a 10 gallon, 20H, 20L or 29? I know that bigger is always better. In the high tanks what happens with the area above the multis or could I put some dither fish there since I believe multis remain close to the bottom?