In my experience, if you put big peaceful fish in there with it they tend to gain some confidence. If you do get some they do better in groups of 5 or more for a smallish tank like yours. The side effect of having more then one in that tank is that they will grow slower. This may or may not be what you want. When they establish their pecking order hormones are released into the water that causes the dominant one to grow faster then the rest. I once bought 6 to go in a grow out tank that was a 50gal. They were all 1.5 inches at the time of purchase. A year later the dominant one was 6 inches and the smallest one was almost 3. The rest slotted in there according to their pecking order. I have found that this also holds true for other slow growing fish such as clown loaches. Just my two bits.
